Question

Find all the zeros of the equation.

-4x4 - 44x2 + 3600 = 0
A. 5, -5, 6i, -6i
B. 5, 6i
C. 5, -5, 6i, 0
D. -5, -6i

Answer 1

4x^4+44x^2-3600=0
x^4+11x^2-900=0
x^4+36x^2-25x^2-900=0
x^2(x^2+36)-25(x^2+36)=0
(x^2-25)(x^2+36)=0
so x^2=25,-36
x=5,-5,6i,-6i

Answer 2

Yeah i thought it was a :)

Answer 3

Thanks :)

Answer 4

you are welcome!