Question

Write the following roots as pure imaginary numbers:

Answer 1

Answer:

9i

30√5 i

Step-by-step explanation:

√ -81

= √ 81  * √ -1

= 9i.

5√ -180

= 5i * √ 180

=  5i *  √36 * √5

= 5i * 6 *√5

= 30√5 i.

Answer 2

Answer:

Step-by-step explanation:

$\sqrt{-81}=\sqrt{i^{2}*9^{2}}=9i\\\\\\ 5\sqrt{-180}=5\sqrt{i^{2}*3*3*2*2*5}=5\sqrt{i^{2}*3^{2}*2^{2}*5}=5*i*2*3\sqrt{5}\\=30i\sqrt{5}$