Need some implicit differentiation help

EvanB

Senior member
Nov 3, 2001
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Hey all,

I have been working on this problem, but cant seem to figure it out. Its been some time since I did implicit diff, and I am struggling. Any idea how to solve:

x+tan(xy)=2

implicitly?

Thanks in advance everyone.

Evan
 

jer0608

Member
Sep 24, 2004
96
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0
I'm a little rusty but I'll give it a shot:

I assume you are trying to solve for dy/dx as a function of x and y

Take the derivative of both sides with respect to x:

d(x)/dx + d[tan(xy)]/dx = d(2)/dx

becomes

1 + (y + x*dy/dx)*[sec(xy)]^2 = 0

Then, solve for dy/dx:

y + x*dy/dx = -1/[sec(xy)]^2 = -[cos(xy)]^2

so

dy/dx = -[y + [cos(xy)]^2]/x


Hope this helps.