Are these the correct expressions for ## dF/dy' ##?

Math100
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Homework Statement
Find the expressions for ## dF/dy' ## when
a) ## F(y')=(1+y'^2)^{\frac{1}{4}} ##
b) ## F(y')=sin (y') ##
c) ## F(y')=exp(y') ##
Relevant Equations
None.
a) ## dF/dy'=\frac{1}{4}(1+y'^2)^{\frac{-3}{4}}\cdot 2y' ##
b) ## dF/dy'=cos (y') ##

I just took the derivatives above and found out these expressions, but may anyone please check/verify to see if these expressions for ## dF/dy' ## are correct? Also, I do not understand part c). What does 'exp' indicate in here?
 
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Math100 said:
Homework Statement: Find the expressions for ## dF/dy' ## when
a) ## F(y')=(1+y'^2)^{\frac{1}{4}} ##
b) ## F(y')=sin (y') ##
c) ## F(y')=exp(y') ##
Relevant Equations: None.

a) ## dF/dy'=\frac{1}{4}(1+y'^2)^{\frac{-3}{4}}\cdot 2y' ##
b) ## dF/dy'=cos (y') ##

I just took the derivatives above and found out these expressions, but may anyone please check/verify to see if these expressions for ## dF/dy' ## are correct? Also, I do not understand part c). What does 'exp' indicate in here?
##\exp(y')## means ##e^{y'}.##

What you wrote is correct, but why is there a prime at the ##y##'s? The same could be written with just ##y## or ##t## as the variable name. ##y'## normally indicates a derivative.
 
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fresh_42 said:
##\exp(y')## means ##e^{y'}.##

What you wrote is correct, but why is there a prime at the ##y##'s? The same could be written with just ##y## or ##t## as the variable name. ##y'## normally indicates a derivative.
I don't know either. So what should the book normally express these primes then, instead? Also, if ## exp(y') ## mean ## e^{y'} ##. Then the expression for ## dF/dy' ## is ## dF/dy'=e^{y'} ##?
 
Math100 said:
I don't know either. So what should the book normally express these primes then, instead? Also, if ## exp(y') ## mean ## e^{y'} ##. Then the expression for ## dF/dy' ## is ## dF/dy'=e^{y'} ##?
Yes.
 
fresh_42 said:
Yes.
Thank you so much for verifying!
 
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