Question

f(x) = 2x^4 − 4x^2 − 48 find the zeros

Answer 1

To find the zeros, let f(x)=0,
\[0=2(x^4-2x^2-24)\]
Hmmmmm it looks like this might factor nicely :)

Answer 2

darnit, too slow!! Follow @zepdrix .... :)

Answer 3

@yabucoayankee

2x^4 − 4x^2 − 48 = 0
Divide through by 2.
x^4 - 2 x^2 - 24 = 0
Look for two numbers that multiply to -24 and sum to -2.

Hint: If you can factor a^2 - 2a - 24, you can factor x^4 - 2 x^2 - 24