Is it possible to factor #y= x^4 -3x^2 -4 #? If so, what are the factors?

1 Answer
Dec 24, 2015

Answer:

Yes. #x = +-2# or #x = +-i#

Explanation:

First represent the equation as a quadratic by substituting # z = x^2#
Then # y = z^2 -3z - 4#
This can be factored as #y = (z- 4)(z+1)#
Therefore #z = 4# or #z = -1#
Given #z =x^2# this means that #x = +-2# or #x = +- sqrt(-1) = +-i#