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

Question #2

http://img830.imageshack.us/img830/8185/0000825.jpg [Broken]

2. Relevant equations

3. The attempt at a solution

I can of course find the derivatives for both functions. When I set them equal to each other I get x=1/2 that's where the functions have parallel tangent lines for the same x value, however (I think that) the functions have parallel tangents everywhere, just at different x values. So I figured out that at any point x on x^2, there will be a parallel tangent from -x^2+2x-5 at 1-x

I guess you have to find the equation of a tangent line that intersects with both graphs only once, no more no less, but I don't know how to write that out and solve for it. The answers are the tangent lines when x = -1 and 2 on x^2

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# Homework Help: Calc I derivatives, I know the answers, but how did I get there?

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