Solve Derivative of y=e^cosx*sinx

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Homework Help Overview

The discussion revolves around finding the derivative of the function y = e^(cos(x)) * sin(x). Participants are exploring the application of differentiation rules in the context of this expression.

Discussion Character

  • Mixed

Approaches and Questions Raised

  • Participants express uncertainty about how to treat the base e in the context of differentiation, questioning whether it should be considered as e^x or in relation to other functions. There are attempts to apply the product and chain rules, with some participants sharing their derivative attempts and reasoning.

Discussion Status

Some participants have provided guidance on the use of the chain and product rules, noting their relevance to the problem. There is acknowledgment of the attempts made, but no consensus on the correctness of the approaches has been reached.

Contextual Notes

Participants are grappling with the definitions and assumptions surrounding the function's components, particularly regarding the treatment of e and its relationship to the derivative process.

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Homework Statement


Find the derivativce of y=e^cosx*sinx

Homework Equations





3. The Attempt at a Solution

i`m just unsure of whether e should be treated as e^x because its not that.. or if e should be treated like an f(x)a^x to f`(x)a^xlna, or if it is still considerd e^x.. here is my attempt.

y`=e^cosx*(-sinx)*(sinx) + (cosx)(e^cosx)

y`= e^cosx(cosx - sin^2x)
 
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Plutonium88 said:

Homework Statement


Find the derivative of y=e^cosx*sinx

Homework Equations



3. The Attempt at a Solution

i`m just unsure of whether e should be treated as e^x because its not that.. or if e should be treated like an f(x)a^x to f`(x)a^xlna, or if it is still considered e^x.. here is my attempt.

y`=e^cosx*(-sinx)*(sinx) + (cosx)(e^cosx)

y`= e^cosx(cosx - sin^2x)

If you're differentiating y = (sin(x))ecos(x), then what you have done is fine.

Writing ax as ex ln(a) can be helpful at times, but writing e in terms of some other constant generally isn't helpful when differentiating.
 
SammyS said:
If you're differentiating y = (sin(x))ecos(x), then what you have done is fine.

Writing ax as ex ln(a) can be helpful at times, but writing e in terms of some other constant generally isn't helpful when differentiating.
Ah i just realized something... e^x = e^cosx in the sense that cosx is `x`. right?

And also thank you for your help.
 
Plutonium88 said:

Homework Equations

The chain rule. ##(f\circ g)'(x)=f'(g(x))g'(x)##
The product rule. ##(fg)'(x)=f'(x)g(x)+f(x)g'(x)##


Plutonium88 said:
i`m just unsure of whether e should be treated as e^x because its not that..
Keep in mind that ##e^{f(x)}=exp(f(x))=(\exp\circ f)(x)##. So you will need the chain rule. You will also need the product rule to find f'(x).
 
Fredrik said:
The chain rule. ##(f\circ g)'(x)=f'(g(x))g'(x)##
The product rule. ##(fg)'(x)=f'(x)g(x)+f(x)g'(x)##



Keep in mind that ##e^{f(x)}=exp(f(x))=(\exp\circ f)(x)##. So you will need the chain rule. You will also need the product rule to find f'(x).

all right, thanks man.
 

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