Trigonometry: Sin, Cos, and Tan
Trigonometry is all about the relationships between angles and sides in right-angled triangles. Think of it as a way to find missing information when you only know part of the puzzle.
The three main trigonometric ratios are sine (sin), cosine (cos), and tangent (tan). Here's what each one represents: sin = opposite ÷ hypotenuse, cos = adjacent ÷ hypotenuse, and tan = opposite ÷ adjacent.
Remember that the hypotenuse is always the longest side (opposite the right angle), the opposite side is across from your angle, and the adjacent side is next to your angle. A handy memory trick is "SOH CAH TOA" - it contains the first letters of each ratio.
You'll also need to memorise exact values for common angles like 30°, 45°, and 60°. These pop up frequently in exams, so knowing them off by heart will save you time and marks.
Quick Tip: Always label your triangle sides (opposite, adjacent, hypotenuse) before choosing which ratio to use - it prevents silly mistakes!