Question

Limit as x approaches 9 of x^2 -81/sqrt of x - 3

Answer 1

108

Explanation:

Limit as x approaches 9 of x^2 -81/sqrt of x - 3

First substitute x into the expression

= 9²-81/√9 - 3

= 81-81/3-3

= 0/0 (indeterminate)

Apply l'hospital rule

= lim x -> 9 d/dx(x²-81)/√x - 3

= lim x -> 9 2x/1/2√x

Substitute x = 9

= 2(9)/1/2√9

=18/1/(2(3)

=18 × 6/1

= 108

Hence the limit of the function is 108