/pi*x\
x*sin|----|
\ 2 /
d / /pi*x\\ --|x*sin|----|| dx\ \ 2 //
Apply the product rule:
; to find :
Apply the power rule: goes to
; to find :
Let .
The derivative of sine is cosine:
Then, apply the chain rule. Multiply by :
The derivative of a constant times a function is the constant times the derivative of the function.
Apply the power rule: goes to
So, the result is:
The result of the chain rule is:
The result is:
Now simplify:
The answer is:
/pi*x\
pi*x*cos|----|
\ 2 / /pi*x\
-------------- + sin|----|
2 \ 2 /
/ /pi*x\ \ | pi*x*sin|----| | | \ 2 / /pi*x\| pi*|- -------------- + cos|----|| \ 4 \ 2 //
2 / /pi*x\ /pi*x\\
-pi *|6*sin|----| + pi*x*cos|----||
\ \ 2 / \ 2 //
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