(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Given f(x)=sqrt(2x+2)

Question : Find the linear approximation of f(x) at a=7 AND use it to approximate sqrt(18).

2. Relevant equations

L(x)=f(a)+f'(a)(x-a)

3. The attempt at a solution

Using the linear approximation formula I am getting the value 6.75, but when I checked with calculator the value of sqrt(18) is 4.2426....

Did my approximation is wrong?

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# Homework Help: Linear approximation

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