What is the domain of the function

Question

f(x)=√(x²-100)?

Answer 1

f(x) = √(x² - 100)

Forbidden values: √(x² - 100) = 0

Take square each side.

x² - 100 = 0.

Add 100 to each side.

x² = 100

Take square root each side.

x = √100 = ± 10

Domain = ℛ \ { -10 ; 10 }.