How Do You Differentiate Complex Functions Like y=sin(lnx) and Others?

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To differentiate complex functions like y=sin(lnx), the chain rule is essential, which involves differentiating from the outside in. The derivative of lnx is 1/x, and the derivative of sin(x) is cos(x), which can be applied in this context. Logarithmic differentiation can also be useful, particularly for functions like y=10^(x^2-sinx). The discussion emphasizes that recognizing the structure of the function helps in applying the chain rule effectively. Understanding these principles aids in tackling similar differentiation problems.
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10. y=sin(lnx) find y'

im not sure how to do this, the previews question was actually with y=ln(sinx), which i know how to do, but not this one.

I know that the derivative of lnx is 1/x and the derivative of sinx=cosx



16.y=10[(x)2-sinx] find y'

PD: that is 10 to the power of (x2-sinx)



i know i should put a ln at both sides of the equation to use logarithmic differentiation, i know the logarithm properties. However, i don't know how should i apply all of that exactly.



EDIT: i also need help finding y' in y=x3-ln(x/e)


Thanks.
 
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The questions are very similar. The rule is known as the chain rule. The best way to describe is that you chain your way from the outside to the inside. If you know how to find y' for:
y = ln(sin(x))

Then you know how to find y' for:
y = sin(ln(x))

For the chain rule, if you have:
u = f(g(x))
\frac{du}{dx} = \frac{df}{dg} \frac{dg}{dx}

Does this help at all?
 
Ignea_unda said:
The questions are very similar. The rule is known as the chain rule. The best way to describe is that you chain your way from the outside to the inside. If you know how to find y' for:
y = ln(sin(x))

Then you know how to find y' for:
y = sin(ln(x))

For the chain rule, if you have:
u = f(g(x))
\frac{du}{dx} = \frac{df}{dg} \frac{dg}{dx}

Does this help at all?


well yeah, all of the qustions kinda looked to chain rules like me, maybe not so ''strongly'' but they did.

Thanks.
 
No worries. Sometimes it just takes a fresh glance to see it.

Glad I could help.
 
Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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