How do you factor by grouping #8r^3 - 64r^2 + r -8#?

1 Answer
Apr 25, 2018

#(8r^2+1)(r-8)#

Explanation:

In grouping, separate the first two terms (in this case, #8r^3# and #-64r^2#) from the second two terms (in this case, #r# and #-8#):

#(8r^3-64r^2)+(r-8) rarr# Factor out the GCF from each of the pairs in the parentheses

#8r^2(r-8)+1(r-8) rarr# Combine the #8r^2# and #1#

#(8r^2+1)(r-8)#