Answer: Find Tangent & Normal Line of y=√x/(x+1) at (4, 0.4)

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Homework Statement


Find the tangent and normal line through the curve at the given point.
y = \frac{\sqrt{x}}{x+1}
Through point (4, 0.4)

Homework Equations



The Attempt at a Solution



Now, I calculate y' to be:

y' = \frac{-(x-1)}{2\sqrt{x}(x+1)^2}

and so:

y'(4) = (-3/100)

That is the slope at x=4 on the curve y?
 
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I don't see the problem. The slope is -3/100 at the point (4,f(4))=(4,.4).
 
Yeah as soon as I clicked submit I realized what the problem with my thinking was. It's time to take a break for the day..

Thanks for the help!
 
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