Question

Express the radical using the imaginary unit, i. ± -81 =±

Answer 1

Step-by-step explanation:

Step 1:  Find the radical

$\pm\sqrt{-81}$

$\pm(\sqrt{-1} * \sqrt{81})$

$\pm i*9$

$\pm 9i$

Answer:  $\pm 9i$

Answer 2

Answer:

+/- 9i

Step-by-step explanation:

+/- sqrt(-81) = +/- sqrt(-1) × sqrt(81)

= +/- 9i