# How do you write 3x^2(2x^3 – 4x^2) in standard form?

Jun 28, 2017

$6 {x}^{5} - 12 {x}^{4}$

#### Explanation:

The formula for expanding $a \left(b + c\right)$ is $a b + a c$. In this exanple a=3x^2; b=2x^3; and $c = - 4 {x}^{2}$.

That leaves us with $3 {x}^{2} \left(2 {x}^{3}\right) + 3 {x}^{2} \left(- 4 {x}^{2}\right)$.

To multiply $a {x}^{b}$ by $c {x}^{d}$, we do $\left(a \cdot c\right) {x}^{b + d}$. Putting our values in, we get $\left(3 \cdot 2\right) {x}^{2 + 3} = 6 {x}^{5}$. Now by doing $3 {x}^{2} \left(- {4}^{2}\right)$, we get $\left(3 \cdot - 4\right) {x}^{2 + 2} = \left(- 12\right) {x}^{4} = - 12 {x}^{4}$.

By adding both values together we get $6 {x}^{5} - 12 {x}^{4}$.