Write in Standard Form (-3i)(10i)

$(- 3 i) (10 i)$

Multiply $(- 3 i) (10 i)$ .

Multiply $10$ by $- 3$ .

$- 30 i i$

Raise $i$ to the power of $1$ .

$- 30 (i^{1} i)$

Raise $i$ to the power of $1$ .

$- 30 (i^{1} i^{1})$

Use the power rule $a^{m} a^{n} = a^{m + n}$ to combine exponents.

$- 30 i^{1 + 1}$

Add $1$ and $1$ .

$- 30 i^{2}$

Rewrite $i^{2}$ as $- 1$ .

$- 30 \cdot - 1$

Multiply $- 30$ by $- 1$ .

$30$