Question

1/8x^3-(1/2x-a^2)*(1/4x^2+1/2a^2x+a^4)

Answer 1

$frac{1}{8} x^{3} -( frac{1}{2}x- a^{2} )( frac{1}{4} x^{2} + frac{1}{2} a^{2}x+ a^{4})= frac{1}8} x^{3} -[( frac{1}{2}x) ^{3} -( a^{2}) ^{3}= frac{1}{8} x^{3} - frac{1}{8} x^{3}$$+ a^{6} = a^{6}$