What do I do in this problem?

Ghost3k

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Nov 4, 2011
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Ok so my professor gave us some hw, and he did not mention it in his class, but I still want to know how to do it. So can anyone tell me what exactly am I supposed to do in this problem. Not the answers, just the steps that I need to do to get the answers. Here is the question.

Find a linearization function and approximate a.
dc77fa7f5472fa83cdcdbe31390d9f1.png
and b.
52a0fb699c3fed1e718e09da9a64cd1.png


The linearization function is

a. The approximation of
dc77fa7f5472fa83cdcdbe31390d9f1.png
is

b. The approximation
52a0fb699c3fed1e718e09da9a64cd1.png
is
 
The idea is to use \(\displaystyle f(x_{0}+ \Delta x)\approx f(x_{0})+f'(x_{0})\Delta x\)

Let's start with \(\displaystyle f(x)=\sqrt{x}\)

Then, \(\displaystyle x_{0}=9, \;\ \Delta x=.02\)

\(\displaystyle f'(x)=\frac{1}{2\sqrt{x}}\)

So, using the formula at the top, we get:

\(\displaystyle f(9.02)\approx f(9)+f'(9)(.02)\)

\(\displaystyle \sqrt{9.02}\approx \sqrt{9}+\frac{1}{2\sqrt{9}}(.02)\)

See now what to do?. Now, try it with 8.99
 
The idea is to use \(\displaystyle f(x_{0}+ \Delta x)\approx f(x_{0})+f'(x_{0})\Delta x\)

Let's start with \(\displaystyle f(x)=\sqrt{x}\)

Then, \(\displaystyle x_{0}=9, \;\ \Delta x=.02\)

\(\displaystyle f'(x)=\frac{1}{2\sqrt{x}}\)

So, using the formula at the top, we get:

\(\displaystyle f(9.02)\approx f(9)+f'(9)(.02)\)

\(\displaystyle \sqrt{9.02}\approx \sqrt{9}+\frac{1}{2\sqrt{9}}(.02)\)

See now what to do?. Now, try it with 8.99

thank you, I understand what I need to do.

So essentially it would be
\(\displaystyle \sqrt{8.99}\approx \sqrt{9}+\frac{1}{2\sqrt{9}}(.01)\) correct?
 
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