What is the standard form of  y= (x + 2)(x + 1)^2 ?

$y = {x}^{3} + 4 {x}^{2} + 5 x + 2$

Explanation:

From the given equation $y = \left(x + 2\right) {\left(x + 1\right)}^{2}$

$y = \left(x + 2\right) {\left(x + 1\right)}^{2}$

just multiply all the terms then simplify

$y = \left(x + 2\right) \left({x}^{2} + 2 x + 1\right)$

$y = {x}^{3} + 2 {x}^{2} + x + 2 {x}^{2} + 4 x + 2$

$y = {x}^{3} + 4 {x}^{2} + 5 x + 2$

God bless...I hope the explanation is useful.