Question

URGENT i rly need help, I'd appreciate it so much:)

use rational root theorem to find the x intercepts, y intercepts, and end behavior
f(x)=x^4-3x^2 - 4

Answer 1

By Rational Root Thoeorem,
q = +-1 and p = +-1, +-2, +-4.
So the possible roots are, p/q = +-1, +-2, +-4.

To test which roots are actual roots, simply plug these values into x, and see which ones of them output 0. After some easy calculation, only x = 2 and x = -2 will make f(x) outputs 0.

To find y intercept, set x to 0, f(x) = -4.

As for the end points behavior, since the highest term is +, and the power is even, meaning that the ends are both going to positive infinity.