Question

(2a+1)cube +(a-1)cube

Answer 1

Answer:

Step-by-step explanation:

=(2a+1)^3 +(a-1)^3

={(2a)^3+3(2a)^2(1) + 3(2a)(1)^2+(1)^3 } +(a)^3-3(a)^2(1)+3(a)(1)^2 +(1)^3

=( 8a^3 + 12a^2+6a+1). +. (a^3 -3a^2+3a -1)

=(8a^3 + a^3 +12a^2-3a^2 +6a + 3a +1-1)

=(9a^3 +9a^2 +9a)