Question

Which of the following are square roots of the number below ? check all that apply

81

a. 18
b.-(81)^1/2
c.9
d.81^1/2

Answer 1

The answers are:
b.-(81)^1/2
c.9
d.81^1/2

√a = -a^1/2 ⇒ √81 = -81^1/2
√a = a^1/2 ⇒ √81 = 81^1/2

√81 = √9²
√a² = a ⇒ √9² = 9
√a² = -a ⇒ √9² = -9