Question

Write the following roots as pure imaginary numbers:

√ -81

5√ -180

someone help me please!!!!

Answer 1

9i

30√5 i

Explanation:

√ -81

= √ 81 * √ -1

= 9i.

5√ -180

= 5i * √ 180

= 5i * √36 * √5

= 5i * 6 *√5

= 30√5 i.

Answer 2

Explanation:

`√(-81)=\sqrt{i^(2)*9^(2)}=9i\\\\\\ 5√(-180)=5\sqrt{i^(2)*3*3*2*2*5}=5\sqrt{i^(2)*3^(2)*2^(2)*5}=5*i*2*3√(5)\\=30i√(5)`