\(a.=x^3+1^3=\left(x+1\right)\left(x^2-x+1\right)\)
\(b.=\left(2a\right)^3-3^3=\left(2a-3\right)\left(2a^2b^2+3\cdot2a+3^2\right)\)
\(=\left(2a-3\right)\left(4a^2+6a+9\right).\)
`a, (x+1)(x^2-x+1)`
`b, (2a-3)(4a^2 + 6a + 9)`
a) \(x^3+1=\left(x+1\right).\left(x^2-x+1\right)\)
b) \(8a^3-27=\left(2a\right)^3-3^3=\left(2a-3\right).\left[\left(2a\right)^2+6a+9\right]\)