How do you factor #y=5x^4+10x^2-15# ?

1 Answer
Mar 2, 2016

Answer:

First factor you can take out is #5#

Explanation:

#=5(x^4+2x^2-3)#

Now if you see #x^2# as a whole (let's call #x^2=z# just for now) you have a quadratic expression you can factor further:
#=5(z^2+2z-3)=5(z+3)(z-1)#

Translated back, this becomes:
#=5(x^2+3)(x^2-1)#

And you can factor the last term even further:
#=5(x^2+3)(x-1)(x+1)#