Math Is Fun Forum

tempos

Member

Registered: 2006-11-24

Posts: 1

Tangent line question

I am to a find the equation to the tangent line of two parabollas. They all have the same slope. When I equate their derivatives my terms disappear.  What do I do then? Need to find points of tangency of both parabollas
f(x) =1-x², g(x)= -x²+8x-12

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Tangent line question

Hi tempos;

Here is a really nice tangent line to both parabolas.

Nice the way it touches the top of the two parabolas!

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