End Behavior of Odd-Degree Polynomials
Odd-degree polynomials (like x³, x⁵) have ends pointing in opposite directions, creating a crossing graph. The leading coefficient determines which end points upward:
If the leading coefficient is positive, the right end points upward and the left end points downward. This means as x→∞, f(x)→∞ and as x→-∞, f(x)→-∞.
If the leading coefficient is negative, the right end points downward and the left end points upward. As x→∞, f(x)→-∞ and as x→-∞, f(x)→∞.
The page shows example problems where students identify end behavior and y-intercepts. For instance, f(x) = 2x⁴+x³-x²+5x+3 has degree 4 with positive leading coefficient, so both ends point upward, and its y-intercept is (0,3).
🔑 Remember: For odd-degree polynomials, the ends always point in opposite directions - one up and one down. The leading coefficient tells you which is which!
The y-intercept is always found by substituting x=0 into the function.