Question

(x+2/3)^3+(x-2/3)^3 simplify please answer properly​

Answer 1

Answer:

(x+2/3)^3+(x-2/3)^3

={(x+2/3)+(x-2/3)}^3-3.(x+2/3)(x-2/3){(x+2/3)+(x-2/3)}

=(x+2/3+x-2/3)^3-3{(x)^2-(2/3)^2}(x+2/3+x-2/3)

=(x+x)^3-3(x^2-4/9).2x

=(2x)^3-6x(x^2-4/9)

=8x^3-6x^3+4.6.x/9

= 2x^3+8x/3