Date: 11/4/96 at 12:29:14 From: Scott Thompson Subject: Implicit Differentiation Here's my question: Find the slope of the tangent at the point (3,4) on the circle x^2 + y^2 = 25. My answer: I guess we would need to put it in the y = mx + b form. Thanks for any help, Scott
Date: 11/05/96 From: Doctor Pete Subject: Re: Implicit Differentiation To find the slope of the tangent at the point (3,4) on the circle x^2 + y^2 = 25 you need to use implicit differentiation. You cannot put a circle into the form of a line. In particular, you want to find dy/dx: d/dx[x^2 + y^2 = 25] ==> 2x + 2y dy/dx = 0. Can you complete the solution? -Doctor Pete, The Math Forum Check out our web site! http://mathforum.org/dr.math/
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