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devin8721
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The surface given by x = x^2 - y^2 is cut by a plane give by y = 3x. producing a curve in the plane. Find the slope of this curve at the ppoint (1,3,-8)
A) 3
B) -16
C) - 8sqrt(2/5)
D) 0
E) 18/sqrt(10)
So we want to look at this curve when y = 3x. Then x = x^2 -y^2 becomes x = x^2 - (3x)^2 which gives x = x^2 - 9x^2.
So we have x = -8x^2 or -8x^2 - x = 0.
The derivative is then - 16x - 1. At the point (1,3,-8) we should should have the derivative equal to
-17 which is not a choice..
Can someone tell me if I did something wrong.
A) 3
B) -16
C) - 8sqrt(2/5)
D) 0
E) 18/sqrt(10)
So we want to look at this curve when y = 3x. Then x = x^2 -y^2 becomes x = x^2 - (3x)^2 which gives x = x^2 - 9x^2.
So we have x = -8x^2 or -8x^2 - x = 0.
The derivative is then - 16x - 1. At the point (1,3,-8) we should should have the derivative equal to
-17 which is not a choice..
Can someone tell me if I did something wrong.