Find the derivative of `"f"("x")="x"^2-2" a t x"=10`

Options

A. 10
B. 20
C. 100
D. 98

Answer

B

Explanation

We have given the function `x^2-2` ,

Then `f(x)=x^2-2`

Now by derivative formula,

`f'(a)=lim(h->0)(f(a+h)-f(a))/h`

`f'(a)=lim(h->0)(((a+h)^2-2)-(a^2-2))/h`

At `x=a=10`

`f'(10)=lim(h->0)(((10+h)^2-2)-(10^2-2))/h`

`f'(10)=lim(h->0)((10^2+h^2+20h-2)-(10^2-2))/h`

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