Is This the Correct Method for Finding dy/dx of y = ln(sin^{-1}(x))?

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The discussion focuses on finding the derivative dy/dx for the function y = ln(sin^{-1}(x)). The method used involves implicit differentiation and checks out with ordinary differentiation, confirming its validity. The participant expresses uncertainty about transferring y during differentiation, questioning if they were differentiating the same equation. Others reassure that the approach is correct and suggest that applying the chain rule could also be a valid method. Overall, the participant feels more confident in their differentiation skills but remains cautious about potential mistakes.
monet A
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To find dy/dx for

y = ln(sin^{-1}(x))

I did this:

<br /> y = ln(sin^{-1}(x)) <br />

so

<br /> e^y = (sin^{-1}(x)) <br />

and

<br /> e^y \frac {dy}{dx} = \frac {1} {\sqrt{1-x^2}} <br />

then

<br /> \frac {dy}{dx} = \frac {1}{\sqrt {1-x^2} * e^y} <br />

<br /> = \frac {1}{\sqrt {1-x^2} * e^{ln(sin^{-1}(x))}} <br />

<br /> = \frac {1}{\sqrt {1-x^2} * (sin^{-1}(x))}} <br />

I think that its all valid implicit differentiation but I m not 100% confident about it, please help.

:frown:
 
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It looks fine to me, and the result checks out with ordinary differentiation. Which part were you uncertain about ?
 
You could have just as easily applied the chain rule but that seems to be fine :smile:
 
hypermorphism said:
It looks fine to me, and the result checks out with ordinary differentiation. Which part were you uncertain about ?

Just the validity of transferring y to differentiate both sides, I wasn't sure that I was differentiating the same equation, probably over thinking it.

Thanks heaps though because I think I am starting to become more capable with it but I don't want to be overconfident in mistakes.

:cool:
 
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