How do you factor by grouping #t^3 + 6t^2 - 2t - 12#?

1 Answer
Apr 28, 2015

Group #t^3 # and 6t^2 # like this,

#t^2(t+6)#

then group #-2t # and #-12 # like this,

#-2(t+6)#

Now add the two,

#t^2(t+6)-2(t+6) => (t^2-2)(t+6)#

Now, further #t^2-2# is a difference of two squares so you factorize thus,

#t^2-2=(t-sqrt(2))(t+sqrt(2))#

So, the final result is #(t-sqrt(2))(t+sqrt(2))(t+6)#