How do you factor 6y6−5y3−4 ?
1 Answer
May 7, 2018
Explanation:
using a substitution reduces the expression to a
usual quadratic
let u=y3
⇒6y6−5y3−4=6u2−5u−4
using the a-c method for factoring
the factors of the product 6×−4=−24
which sum to - 5 are + 3 and - 8
split the middle term using these factors
6u2+3u−8u−4←factor by grouping
=3u(2u+1)−4(2u+1)
take out the common factor (2u+1)
=(2u+1)(3u−4)
change the substitution back into terms in y
⇒6y6−5y3−4=(2y3+1)(3y3−4)