Find the approximate value of `sqrt(8.95)`

Explanation

Let `f(x)=sqrt(x), :. f'(x)=(1)/(2sqrt(x))`
Take a = 9 and h = -0.05. Then `f(a)=f(9)=sqrt(9)=3` and
`f'(a)=f'(9)=(1)/(2sqrt(9))=(1)/(6)`.
The formula for approximation is
`f(a+h)=f(a)+h.f'(a)`
`:.sqrt(8.95)=f(9-0.05)`
`=f(9)-(0.05)f'(9)`
`=3-0.05xx(1)/(6)`
`=3-0.0083=2.9917`
`:.sqrt(8.95)=2.9917`.