Question

Between what positive integral values of x does P(x) = x^4 + 2x^2 - 8 have a real zero?

pretty please :) :)

Answer 1

P(0) = -8
P(2) = 16
so between x = 0 and x = 2, there is a real zero (since y is negative at x = 0 and y is positive at x = 16, so it cross the x axis somewhere in between)