2 log (x*sin(x) + cos(x)) ----------------------- 2
log(x*sin(x) + cos(x))^2/2
The derivative of a constant times a function is the constant times the derivative of the function.
Let .
Apply the power rule: goes to
Then, apply the chain rule. Multiply by :
Let .
The derivative of is .
Then, apply the chain rule. Multiply by :
Differentiate term by term:
Apply the product rule:
; to find :
Apply the power rule: goes to
; to find :
The derivative of sine is cosine:
The result is:
The derivative of cosine is negative sine:
The result is:
The result of the chain rule is:
The result of the chain rule is:
So, the result is:
The answer is:
x*cos(x)*log(x*sin(x) + cos(x)) ------------------------------- x*sin(x) + cos(x)
/ 2 2 2 2 \ | x *cos (x) x *cos (x)*log(x*sin(x) + cos(x))| -|-cos(x)*log(x*sin(x) + cos(x)) + x*log(x*sin(x) + cos(x))*sin(x) - ----------------- + ---------------------------------| \ x*sin(x) + cos(x) x*sin(x) + cos(x) / ---------------------------------------------------------------------------------------------------------------------------- x*sin(x) + cos(x)
/ 2 3 3 3 3 2 2 2 \ | 3*x*cos (x) 3*x *cos (x) 2*x *cos (x)*log(x*sin(x) + cos(x)) 3*x*cos (x)*log(x*sin(x) + cos(x)) 3*x *cos(x)*sin(x) 3*x *cos(x)*log(x*sin(x) + cos(x))*sin(x)| -|2*log(x*sin(x) + cos(x))*sin(x) + x*cos(x)*log(x*sin(x) + cos(x)) - ----------------- + -------------------- - ----------------------------------- + ---------------------------------- + ------------------ - -----------------------------------------| | x*sin(x) + cos(x) 2 2 x*sin(x) + cos(x) x*sin(x) + cos(x) x*sin(x) + cos(x) | \ (x*sin(x) + cos(x)) (x*sin(x) + cos(x)) / ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ x*sin(x) + cos(x)