Question

Given that f(x)=x^2-1
A) find f(5)
B) find f^-1(x)
C)f^-1(8)

Answer 1

Answer:

a)  f(5) = 24

b) The inverse of given function

              f⁻¹ ( x ) = √x+1

c)    f⁻¹ ( 8 ) = √9 =3

Step-by-step explanation:

Explanation:-

Given  f(x) = x² - 1

a)

      f(5) = 5² -1 = 25-1 =24

b)      

put y =  f(x) = x² - 1

   ⇒   y =  x² - 1

 ⇒     x² = y + 1

⇒     x = √y+1

⇒ f⁻¹ ( y ) = √y+1      ( ∵ f⁻¹ ( y) =x)

The inverse of given function

              f⁻¹ ( x ) = √x+1

c)   put x=8

             f⁻¹ ( 8 ) = √8+1 = √9 =3