Trying to find dy/dx of a trig function

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Homework Statement


find dy/dx


Homework Equations


x= tan y


The Attempt at a Solution


d/dx(x=tanY)

1=(tan(dy/dx))+sec^2+y
 
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jtt said:

Homework Statement


find dy/dx


Homework Equations


x= tan y


The Attempt at a Solution


d/dx(x=tanY)
First off, you don't take the derivative of an equation - you take the derivative of each side of an equation.

The above should be d/dx(x) = d/dx(tan(y))

To carry out the differentiation on the right, you need to use the chain rule.

d/dx(f(u)) = d/du(f(u)) * du/dx = f'(u) * du/dx
jtt said:
1=(tan(dy/dx))+sec^2+y
Nope.
 
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