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

The tangent line through given points (pi/4,pi/4) m=1

y= cos(y)cos(x)/sin(x)sin(y)

3. The attempt at a solution

dy/dx= d/dx[cos(y)cos(x)/sin(x)sin(y)]

First use quotient rule ?

vu'-uv'/v^2

v= sin(x)sin(y)

v'= do i need to use product rule? for product rule I got sin(x)*cos(x)+sin(x)*cos(x)

but if I do it normal way, I get cos(x)*sin(y)

u= cos(y)cos(x)

u'= -sin(x)cos(y)

Quotient Rule:

sin(x)sin(y)*-sin(x)cos(y) - cos(y)cos(x)*cos(x)*sin(y)

sin(x)sin(y)^2

I just need to know if I'm going in the right direction. I'm pretty sure I know what to do for the point slope formula since its basic algebra. But it's this beginning part that I have problems with ! Thanks in advance :)

1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

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# Homework Help: Quick Tangent Line Approximation (Derivatives)

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