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Basic Algebra and Geometry Formulas PDF with Examples

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Basic Algebra and Geometry Formulas PDF with Examples

This comprehensive guide covers essential algebraic formulas and geometric formulas for students, including special products, quadratic equations, means, progressions, and various geometric shapes. It provides a thorough overview of key concepts in basic algebra and geometry with clear explanations and formulas.

8/11/2023

390

Special Products
a(x + y) = ax + ay
(x + a)(x + b) = x² + (a + b)x + ab
(x+y)(x - y) = x² - y²
(x + y)² = x² + 2xy + y²
(x - y)² = x² - 2xy

Solid Geometry Formulas

This page presents volume and surface area formulas for various three-dimensional shapes, essential for students studying solid geometry.

The following shapes are covered:

  1. Prism: V = Bh, SA = 2B + Ph
  2. Cylinder: V = πr²h, SA = 2πr² + 2πrh
  3. Cone: V = (1/3)πr²h, SA = πr² + πrl
  4. Pyramid: V = (1/3)Bh, SA = B + (1/2)Pl
  5. Frustum: V = (h/3)(B₁ + B₂ + √(B₁B₂)), SA = B₁ + B₂ + (1/2)(P₁ + P₂)l
  6. Prismatoid: V = (h/6)(A₁ + 4Aₘ + A₂)
  7. Truncated prism: V = (A/3)(h₁ + h₂ + h₃)

Definition: A frustum is the portion of a solid (usually a cone or pyramid) lying between two parallel planes cutting the solid.

The page also includes formulas for spheres and related shapes:

  • Sphere: V = (4/3)πr³, SA = 4πr²
  • Spherical zone: SA = 2πRh
  • Spherical segment (1 base): V = (πh/6)(3R - h), SA = B + Z
  • Spherical segment (2 bases): V = (πh/6)(3a² + 3b² + h²), SA = B₁ + B₂ + Z
  • Spherical sector: V = (ZR)/3
  • Spherical wedge: V = (2/3)r³θ (θ in radians)
  • Spherical lune: SA = 2r²θ (θ in radians)

Example: For a sphere with radius 5 cm:

  • Volume = (4/3)π(5³) ≈ 523.6 cm³
  • Surface Area = 4π(5²) ≈ 314.2 cm²
Special Products
a(x + y) = ax + ay
(x + a)(x + b) = x² + (a + b)x + ab
(x+y)(x - y) = x² - y²
(x + y)² = x² + 2xy + y²
(x - y)² = x² - 2xy

View

Special Products and Quadratic Formulas

This page introduces fundamental algebraic formulas for special products and quadratic equations, essential for students studying basic algebra.

The special product formulas cover various algebraic expansions, including:

  • Distributive property: a(x + y) = ax + ay
  • Binomial products: (x + a)(x + b) = x² + (a + b)x + ab
  • Difference of squares: (x + y)(x - y) = x² - y²
  • Perfect square trinomials: (x + y)² = x² + 2xy + y²
  • Cube of binomials: (x + y)³ = x³ + 3x²y + 3xy² + y³

The quadratic formula for solving equations in the form ax² + bx + c = 0 is presented: x = [-b ± √(b² - 4ac)] / (2a)

Definition: The discriminant (D = b² - 4ac) determines the nature of the roots:

  • D > 0: Two distinct real roots
  • D = 0: One repeated real root
  • D < 0: Two complex conjugate roots

Highlight: Understanding these special product formulas and the quadratic formula is crucial for solving a wide range of algebraic problems in higher mathematics.

Special Products
a(x + y) = ax + ay
(x + a)(x + b) = x² + (a + b)x + ab
(x+y)(x - y) = x² - y²
(x + y)² = x² + 2xy + y²
(x - y)² = x² - 2xy

View

Quadrilateral Area Formulas

This page focuses on area formulas for various types of quadrilaterals, expanding on geometric formulas for plane figures.

The following quadrilaterals are covered:

  1. Trapezoid: A = (1/2)(b₁ + b₂)h, where b₁ and b₂ are the parallel sides and h is the height
  2. Kite: A = (1/2)d₁d₂, where d₁ and d₂ are the diagonals
  3. Parallelogram: Multiple formulas provided, including A = bh and A = (1/2)d₁d₂ sin θ
  4. Rhombus: Formulas include A = xh and A = (1/2)d₁d₂

Vocabulary: A kite is a quadrilateral with two pairs of adjacent sides that are equal in length.

For general quadrilaterals, more advanced formulas are presented:

  • Bretschneider's formula: A = √[(s-a)(s-b)(s-c)(s-d) - abcd cos²((A+C)/2)]
  • Brahmagupta's formula (for cyclic quadrilaterals): A = √[(s-a)(s-b)(s-c)(s-d)]

Highlight: Ptolemy's theorem for cyclic quadrilaterals states that the product of the diagonals equals the sum of the products of opposite sides: d₁d₂ = ac + bd.

The page concludes with formulas for quadrilaterals circumscribing a circle and the area given diagonals and their angle of intersection.

Special Products
a(x + y) = ax + ay
(x + a)(x + b) = x² + (a + b)x + ab
(x+y)(x - y) = x² - y²
(x + y)² = x² + 2xy + y²
(x - y)² = x² - 2xy

View

Circle and Regular Polygon Formulas

This page presents formulas related to circles and regular polygons, essential components of basic geometry.

For circles, the following formulas are provided:

  • Area: A = πr²
  • Circumference: C = 2πr
  • Arc length: L = rθ (θ in radians)
  • Area of a sector: A = (1/2)r²θ
  • Chord length: c = 2√(r² - l²), where l is the distance from the center to the chord

Definition: A sector of a circle is the region bounded by two radii and an arc of the circle.

For regular polygons, the page includes formulas for:

  • Interior angle: (180°(n-2)) / n, where n is the number of sides
  • Exterior angle: 360° / n
  • Number of diagonals: nC₂ - n

Example: For a regular hexagon (n = 6):

  • Interior angle = (180°(6-2)) / 6 = 120°
  • Exterior angle = 360° / 6 = 60°
  • Number of diagonals = 6C₂ - 6 = 9

The page also provides relationships between the apothem, side length, and circumradius of a regular polygon.

Special Products
a(x + y) = ax + ay
(x + a)(x + b) = x² + (a + b)x + ab
(x+y)(x - y) = x² - y²
(x + y)² = x² + 2xy + y²
(x - y)² = x² - 2xy

View

Triangle Area Formulas

This page focuses on various formulas for calculating the area of triangles, a fundamental topic in geometry.

The following area formulas are presented:

  1. Right triangle: A = (1/2)ab, where a and b are the lengths of the legs
  2. Using Heron's formula (SSS): A = √[s(s-a)(s-b)(s-c)], where s is the semi-perimeter
  3. Using trigonometry (SAS): A = (1/2)ab sin C, where C is the included angle
  4. Triangle inscribed in a circle: A = abc / (4R), where R is the radius of the circumscribed circle
  5. Triangle circumscribed around a circle: A = rs, where r is the radius of the inscribed circle
  6. Triangle with an escribed circle: A = r(s-a), where r is the radius of the escribed circle

Highlight: Heron's formula is particularly useful when only the side lengths of a triangle are known, while the SAS formula is helpful when an angle and two sides are given.

The page also includes a formula for calculating the length of a median in a triangle and the area of a five-pointed star.

Vocabulary: The median of a triangle is a line segment that connects a vertex to the midpoint of the opposite side.

Special Products
a(x + y) = ax + ay
(x + a)(x + b) = x² + (a + b)x + ab
(x+y)(x - y) = x² - y²
(x + y)² = x² + 2xy + y²
(x - y)² = x² - 2xy

View

Vieta's Formulas and Types of Means

This page covers Vieta's formulas for polynomial equations and introduces different types of means, expanding on basic algebra and geometry formulas.

Vieta's formulas are presented for quadratic, cubic, and quartic equations, relating the coefficients of a polynomial to sums and products of its roots.

Definition: Vieta's formulas provide a way to express the sums and products of the roots of a polynomial equation in terms of its coefficients.

The page then introduces four types of means:

  1. Arithmetic Mean (AM): The average of a set of numbers
  2. Harmonic Mean (HM): The reciprocal of the arithmetic mean of the reciprocals
  3. Geometric Mean (GM): The nth root of the product of n numbers
  4. Quadratic Mean (QM) or Root Mean Square (RMS): The square root of the arithmetic mean of the squares

Example: For the numbers 2, 4, and 8:

  • AM = (2 + 4 + 8) / 3 = 4.67
  • HM = 3 / (1/2 + 1/4 + 1/8) = 3.43
  • GM = ∛(2 × 4 × 8) = 4
  • QM = √[(2² + 4² + 8²) / 3] = 5.16

The page concludes with formulas for arithmetic and geometric progressions, including terms and sums of finite and infinite series.

Special Products
a(x + y) = ax + ay
(x + a)(x + b) = x² + (a + b)x + ab
(x+y)(x - y) = x² - y²
(x + y)² = x² + 2xy + y²
(x - y)² = x² - 2xy

View

Binomial Expansion and Clock Problems

This page delves deeper into algebraic formulas, focusing on binomial expansions and clock problems.

The binomial expansion formula is presented for (ax + by)ⁿ, including:

  • General term formula
  • Middle term
  • Sum of exponents
  • Sum of coefficients

For clock problems, a formula is provided to calculate the angle between the hour and minute hands:

Angle = |30H - 5.5M|, where H is the hour and M is the minutes

Example: In a clock problem, to find the time when the hands form a right angle (90°), you would solve the equation: |30H - 5.5M| = 90°

The page also introduces the multinomial expansion formula for expressions like (Ax + By + Cz)ⁿ.

Vocabulary: Multinomial expansion extends the concept of binomial expansion to expressions with more than two terms.

Special Products
a(x + y) = ax + ay
(x + a)(x + b) = x² + (a + b)x + ab
(x+y)(x - y) = x² - y²
(x + y)² = x² + 2xy + y²
(x - y)² = x² - 2xy

View

Analytic Geometry: Triangles and Conic Sections

This page continues with analytic geometry, covering triangles defined by coordinates and introducing conic sections.

For triangles defined by coordinates (x₁, y₁), (x₂, y₂), and (x₃, y₃), the following are presented:

  • Area formula using the "basket method"
  • Area formula using matrix determinants
  • Coordinates of the centroid: xc = (x₁ + x₂ + x₃)/3, yc = (y₁ + y₂ + y₃)/3

Vocabulary: The centroid of a triangle is the point where its three medians intersect, dividing each median in a 2:1 ratio.

The page then introduces the general form of conic sections: Ax² + Bxy + Cy² + Dx + Ey + F = 0

When B = 0, the equation simplifies to: Ax² + Cy² + Dx + Ey + F = 0

Definition: Conic sections are curves formed by the intersection of a plane and a double cone. They include circles, ellipses, parabolas, and hyperbolas.

The type of conic section can be determined based on the coefficients:

  1. If A = 0 or C = 0, it's a parabola
  2. If A = C ≠ 0, it's a circle
  3. If A ≠ C and same sign, it's an ellipse
  4. If A ≠ C and different signs, it's a hyperbola

Example: The equation x² + y² = 25 represents a circle with radius 5 centered at the origin.

Highlight: Understanding conic sections is crucial for many applications in physics, engineering, and advanced mathematics.

Special Products
a(x + y) = ax + ay
(x + a)(x + b) = x² + (a + b)x + ab
(x+y)(x - y) = x² - y²
(x + y)² = x² + 2xy + y²
(x - y)² = x² - 2xy

View

Polyhedron Properties

This page provides information on the properties of regular polyhedra, also known as Platonic solids, which are important in solid geometry.

The five Platonic solids are presented with their properties:

  1. Tetrahedron (4 faces)
  2. Hexahedron (cube, 6 faces)
  3. Octahedron (8 faces)
  4. Dodecahedron (12 faces)
  5. Icosahedron (20 faces)

For each polyhedron, the following properties are listed:

  • Number of faces, vertices, and edges
  • Surface area formula
  • Volume formula
  • Radius of inscribed sphere formula

Highlight: Euler's formula for polyhedra that do not intersect themselves: F + V - E = 2, where F is the number of faces, V is the number of vertices, and E is the number of edges.

Example: For a cube with side length s:

  • Surface Area = 6s²
  • Volume = s³
  • Radius of inscribed sphere = s/2

Vocabulary: A regular polyhedron is a three-dimensional solid where all faces are congruent regular polygons, and all vertices are surrounded by the same number of faces.

Special Products
a(x + y) = ax + ay
(x + a)(x + b) = x² + (a + b)x + ab
(x+y)(x - y) = x² - y²
(x + y)² = x² + 2xy + y²
(x - y)² = x² - 2xy

View

Analytic Geometry: Lines and Distances

This page introduces fundamental concepts of analytic geometry, focusing on equations of lines and distance formulas.

Various forms of line equations are presented:

  1. General form: Ax + By + C = 0
  2. Two-point form: (y - y₁)/(y₂ - y₁) = (x - x₁)/(x₂ - x₁)
  3. Point-slope form: y - y₁ = m(x - x₁)
  4. Intercept form: x/a + y/b = 1
  5. Slope-intercept form: y = mx + b
  6. Determinant form: |x y 1| = 0 |x₁ y₁ 1| |x₂ y₂ 1|

Definition: The slope (m) of a line is the change in y divided by the change in x between any two points on the line.

Distance formulas are provided for:

  • Distance between two points: d = √[(x₂ - x₁)² + (y₂ - y₁)²]
  • Midpoint of a line segment: xₘ = (x₁ + x₂)/2, yₘ = (y₁ + y₂)/2
  • Distance from a point to a line: d = |Ax₁ + By₁ + C| / √(A² + B²)

The page also includes formulas for parallel lines and the angle of inclination of a line.

Example: The distance between points (1, 2) and (4, 6) is: d = √[(4 - 1)² + (6 - 2)²] = √(3² + 4²) = 5

Can't find what you're looking for? Explore other subjects.

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Basic Algebra and Geometry Formulas PDF with Examples

This comprehensive guide covers essential algebraic formulas and geometric formulas for students, including special products, quadratic equations, means, progressions, and various geometric shapes. It provides a thorough overview of key concepts in basic algebra and geometry with clear explanations and formulas.

8/11/2023

390

 

12th

 

Calculus 1

50

Special Products
a(x + y) = ax + ay
(x + a)(x + b) = x² + (a + b)x + ab
(x+y)(x - y) = x² - y²
(x + y)² = x² + 2xy + y²
(x - y)² = x² - 2xy

Solid Geometry Formulas

This page presents volume and surface area formulas for various three-dimensional shapes, essential for students studying solid geometry.

The following shapes are covered:

  1. Prism: V = Bh, SA = 2B + Ph
  2. Cylinder: V = πr²h, SA = 2πr² + 2πrh
  3. Cone: V = (1/3)πr²h, SA = πr² + πrl
  4. Pyramid: V = (1/3)Bh, SA = B + (1/2)Pl
  5. Frustum: V = (h/3)(B₁ + B₂ + √(B₁B₂)), SA = B₁ + B₂ + (1/2)(P₁ + P₂)l
  6. Prismatoid: V = (h/6)(A₁ + 4Aₘ + A₂)
  7. Truncated prism: V = (A/3)(h₁ + h₂ + h₃)

Definition: A frustum is the portion of a solid (usually a cone or pyramid) lying between two parallel planes cutting the solid.

The page also includes formulas for spheres and related shapes:

  • Sphere: V = (4/3)πr³, SA = 4πr²
  • Spherical zone: SA = 2πRh
  • Spherical segment (1 base): V = (πh/6)(3R - h), SA = B + Z
  • Spherical segment (2 bases): V = (πh/6)(3a² + 3b² + h²), SA = B₁ + B₂ + Z
  • Spherical sector: V = (ZR)/3
  • Spherical wedge: V = (2/3)r³θ (θ in radians)
  • Spherical lune: SA = 2r²θ (θ in radians)

Example: For a sphere with radius 5 cm:

  • Volume = (4/3)π(5³) ≈ 523.6 cm³
  • Surface Area = 4π(5²) ≈ 314.2 cm²
Special Products
a(x + y) = ax + ay
(x + a)(x + b) = x² + (a + b)x + ab
(x+y)(x - y) = x² - y²
(x + y)² = x² + 2xy + y²
(x - y)² = x² - 2xy

Special Products and Quadratic Formulas

This page introduces fundamental algebraic formulas for special products and quadratic equations, essential for students studying basic algebra.

The special product formulas cover various algebraic expansions, including:

  • Distributive property: a(x + y) = ax + ay
  • Binomial products: (x + a)(x + b) = x² + (a + b)x + ab
  • Difference of squares: (x + y)(x - y) = x² - y²
  • Perfect square trinomials: (x + y)² = x² + 2xy + y²
  • Cube of binomials: (x + y)³ = x³ + 3x²y + 3xy² + y³

The quadratic formula for solving equations in the form ax² + bx + c = 0 is presented: x = [-b ± √(b² - 4ac)] / (2a)

Definition: The discriminant (D = b² - 4ac) determines the nature of the roots:

  • D > 0: Two distinct real roots
  • D = 0: One repeated real root
  • D < 0: Two complex conjugate roots

Highlight: Understanding these special product formulas and the quadratic formula is crucial for solving a wide range of algebraic problems in higher mathematics.

Special Products
a(x + y) = ax + ay
(x + a)(x + b) = x² + (a + b)x + ab
(x+y)(x - y) = x² - y²
(x + y)² = x² + 2xy + y²
(x - y)² = x² - 2xy

Quadrilateral Area Formulas

This page focuses on area formulas for various types of quadrilaterals, expanding on geometric formulas for plane figures.

The following quadrilaterals are covered:

  1. Trapezoid: A = (1/2)(b₁ + b₂)h, where b₁ and b₂ are the parallel sides and h is the height
  2. Kite: A = (1/2)d₁d₂, where d₁ and d₂ are the diagonals
  3. Parallelogram: Multiple formulas provided, including A = bh and A = (1/2)d₁d₂ sin θ
  4. Rhombus: Formulas include A = xh and A = (1/2)d₁d₂

Vocabulary: A kite is a quadrilateral with two pairs of adjacent sides that are equal in length.

For general quadrilaterals, more advanced formulas are presented:

  • Bretschneider's formula: A = √[(s-a)(s-b)(s-c)(s-d) - abcd cos²((A+C)/2)]
  • Brahmagupta's formula (for cyclic quadrilaterals): A = √[(s-a)(s-b)(s-c)(s-d)]

Highlight: Ptolemy's theorem for cyclic quadrilaterals states that the product of the diagonals equals the sum of the products of opposite sides: d₁d₂ = ac + bd.

The page concludes with formulas for quadrilaterals circumscribing a circle and the area given diagonals and their angle of intersection.

Special Products
a(x + y) = ax + ay
(x + a)(x + b) = x² + (a + b)x + ab
(x+y)(x - y) = x² - y²
(x + y)² = x² + 2xy + y²
(x - y)² = x² - 2xy

Circle and Regular Polygon Formulas

This page presents formulas related to circles and regular polygons, essential components of basic geometry.

For circles, the following formulas are provided:

  • Area: A = πr²
  • Circumference: C = 2πr
  • Arc length: L = rθ (θ in radians)
  • Area of a sector: A = (1/2)r²θ
  • Chord length: c = 2√(r² - l²), where l is the distance from the center to the chord

Definition: A sector of a circle is the region bounded by two radii and an arc of the circle.

For regular polygons, the page includes formulas for:

  • Interior angle: (180°(n-2)) / n, where n is the number of sides
  • Exterior angle: 360° / n
  • Number of diagonals: nC₂ - n

Example: For a regular hexagon (n = 6):

  • Interior angle = (180°(6-2)) / 6 = 120°
  • Exterior angle = 360° / 6 = 60°
  • Number of diagonals = 6C₂ - 6 = 9

The page also provides relationships between the apothem, side length, and circumradius of a regular polygon.

Special Products
a(x + y) = ax + ay
(x + a)(x + b) = x² + (a + b)x + ab
(x+y)(x - y) = x² - y²
(x + y)² = x² + 2xy + y²
(x - y)² = x² - 2xy

Triangle Area Formulas

This page focuses on various formulas for calculating the area of triangles, a fundamental topic in geometry.

The following area formulas are presented:

  1. Right triangle: A = (1/2)ab, where a and b are the lengths of the legs
  2. Using Heron's formula (SSS): A = √[s(s-a)(s-b)(s-c)], where s is the semi-perimeter
  3. Using trigonometry (SAS): A = (1/2)ab sin C, where C is the included angle
  4. Triangle inscribed in a circle: A = abc / (4R), where R is the radius of the circumscribed circle
  5. Triangle circumscribed around a circle: A = rs, where r is the radius of the inscribed circle
  6. Triangle with an escribed circle: A = r(s-a), where r is the radius of the escribed circle

Highlight: Heron's formula is particularly useful when only the side lengths of a triangle are known, while the SAS formula is helpful when an angle and two sides are given.

The page also includes a formula for calculating the length of a median in a triangle and the area of a five-pointed star.

Vocabulary: The median of a triangle is a line segment that connects a vertex to the midpoint of the opposite side.

Special Products
a(x + y) = ax + ay
(x + a)(x + b) = x² + (a + b)x + ab
(x+y)(x - y) = x² - y²
(x + y)² = x² + 2xy + y²
(x - y)² = x² - 2xy

Vieta's Formulas and Types of Means

This page covers Vieta's formulas for polynomial equations and introduces different types of means, expanding on basic algebra and geometry formulas.

Vieta's formulas are presented for quadratic, cubic, and quartic equations, relating the coefficients of a polynomial to sums and products of its roots.

Definition: Vieta's formulas provide a way to express the sums and products of the roots of a polynomial equation in terms of its coefficients.

The page then introduces four types of means:

  1. Arithmetic Mean (AM): The average of a set of numbers
  2. Harmonic Mean (HM): The reciprocal of the arithmetic mean of the reciprocals
  3. Geometric Mean (GM): The nth root of the product of n numbers
  4. Quadratic Mean (QM) or Root Mean Square (RMS): The square root of the arithmetic mean of the squares

Example: For the numbers 2, 4, and 8:

  • AM = (2 + 4 + 8) / 3 = 4.67
  • HM = 3 / (1/2 + 1/4 + 1/8) = 3.43
  • GM = ∛(2 × 4 × 8) = 4
  • QM = √[(2² + 4² + 8²) / 3] = 5.16

The page concludes with formulas for arithmetic and geometric progressions, including terms and sums of finite and infinite series.

Special Products
a(x + y) = ax + ay
(x + a)(x + b) = x² + (a + b)x + ab
(x+y)(x - y) = x² - y²
(x + y)² = x² + 2xy + y²
(x - y)² = x² - 2xy

Binomial Expansion and Clock Problems

This page delves deeper into algebraic formulas, focusing on binomial expansions and clock problems.

The binomial expansion formula is presented for (ax + by)ⁿ, including:

  • General term formula
  • Middle term
  • Sum of exponents
  • Sum of coefficients

For clock problems, a formula is provided to calculate the angle between the hour and minute hands:

Angle = |30H - 5.5M|, where H is the hour and M is the minutes

Example: In a clock problem, to find the time when the hands form a right angle (90°), you would solve the equation: |30H - 5.5M| = 90°

The page also introduces the multinomial expansion formula for expressions like (Ax + By + Cz)ⁿ.

Vocabulary: Multinomial expansion extends the concept of binomial expansion to expressions with more than two terms.

Special Products
a(x + y) = ax + ay
(x + a)(x + b) = x² + (a + b)x + ab
(x+y)(x - y) = x² - y²
(x + y)² = x² + 2xy + y²
(x - y)² = x² - 2xy

Analytic Geometry: Triangles and Conic Sections

This page continues with analytic geometry, covering triangles defined by coordinates and introducing conic sections.

For triangles defined by coordinates (x₁, y₁), (x₂, y₂), and (x₃, y₃), the following are presented:

  • Area formula using the "basket method"
  • Area formula using matrix determinants
  • Coordinates of the centroid: xc = (x₁ + x₂ + x₃)/3, yc = (y₁ + y₂ + y₃)/3

Vocabulary: The centroid of a triangle is the point where its three medians intersect, dividing each median in a 2:1 ratio.

The page then introduces the general form of conic sections: Ax² + Bxy + Cy² + Dx + Ey + F = 0

When B = 0, the equation simplifies to: Ax² + Cy² + Dx + Ey + F = 0

Definition: Conic sections are curves formed by the intersection of a plane and a double cone. They include circles, ellipses, parabolas, and hyperbolas.

The type of conic section can be determined based on the coefficients:

  1. If A = 0 or C = 0, it's a parabola
  2. If A = C ≠ 0, it's a circle
  3. If A ≠ C and same sign, it's an ellipse
  4. If A ≠ C and different signs, it's a hyperbola

Example: The equation x² + y² = 25 represents a circle with radius 5 centered at the origin.

Highlight: Understanding conic sections is crucial for many applications in physics, engineering, and advanced mathematics.

Special Products
a(x + y) = ax + ay
(x + a)(x + b) = x² + (a + b)x + ab
(x+y)(x - y) = x² - y²
(x + y)² = x² + 2xy + y²
(x - y)² = x² - 2xy

Polyhedron Properties

This page provides information on the properties of regular polyhedra, also known as Platonic solids, which are important in solid geometry.

The five Platonic solids are presented with their properties:

  1. Tetrahedron (4 faces)
  2. Hexahedron (cube, 6 faces)
  3. Octahedron (8 faces)
  4. Dodecahedron (12 faces)
  5. Icosahedron (20 faces)

For each polyhedron, the following properties are listed:

  • Number of faces, vertices, and edges
  • Surface area formula
  • Volume formula
  • Radius of inscribed sphere formula

Highlight: Euler's formula for polyhedra that do not intersect themselves: F + V - E = 2, where F is the number of faces, V is the number of vertices, and E is the number of edges.

Example: For a cube with side length s:

  • Surface Area = 6s²
  • Volume = s³
  • Radius of inscribed sphere = s/2

Vocabulary: A regular polyhedron is a three-dimensional solid where all faces are congruent regular polygons, and all vertices are surrounded by the same number of faces.

Special Products
a(x + y) = ax + ay
(x + a)(x + b) = x² + (a + b)x + ab
(x+y)(x - y) = x² - y²
(x + y)² = x² + 2xy + y²
(x - y)² = x² - 2xy

Analytic Geometry: Lines and Distances

This page introduces fundamental concepts of analytic geometry, focusing on equations of lines and distance formulas.

Various forms of line equations are presented:

  1. General form: Ax + By + C = 0
  2. Two-point form: (y - y₁)/(y₂ - y₁) = (x - x₁)/(x₂ - x₁)
  3. Point-slope form: y - y₁ = m(x - x₁)
  4. Intercept form: x/a + y/b = 1
  5. Slope-intercept form: y = mx + b
  6. Determinant form: |x y 1| = 0 |x₁ y₁ 1| |x₂ y₂ 1|

Definition: The slope (m) of a line is the change in y divided by the change in x between any two points on the line.

Distance formulas are provided for:

  • Distance between two points: d = √[(x₂ - x₁)² + (y₂ - y₁)²]
  • Midpoint of a line segment: xₘ = (x₁ + x₂)/2, yₘ = (y₁ + y₂)/2
  • Distance from a point to a line: d = |Ax₁ + By₁ + C| / √(A² + B²)

The page also includes formulas for parallel lines and the angle of inclination of a line.

Example: The distance between points (1, 2) and (4, 6) is: d = √[(4 - 1)² + (6 - 2)²] = √(3² + 4²) = 5

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