How do you factor #8x^3+27#?

2 Answers
Mar 7, 2018

You can't factorize it as:
#8x^3=2xx2xx2xx x xx x xx x#
And
#27=3xx3xx3#
Nothing is common....
#1(8x^3+27)# can be written

Apr 7, 2018

Answer:

#color(magenta)(=>[4x^2-6x+9][2x+3]#

Explanation:

#8x^3+27#

#=>(2x)^3+3^3#

Using the identity: #color(red)(a^3+b^3=(a^2-ab+b^2)(a+b)#

#(2x)^3+3^3#

#=>[(2x)^2-(2x xx3)+3^2][2x+3]#

#color(magenta)(=>[4x^2-6x+9][2x+3]#

~Hope this helps! :)