x e *(sin(4*x) + cos(4*x)) ------------------------ 5
/ x \ d |e *(sin(4*x) + cos(4*x))| --|------------------------| dx\ 5 /
The derivative of a constant times a function is the constant times the derivative of the function.
Apply the product rule:
; to find :
Differentiate term by term:
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:
Let .
The derivative of cosine is negative sine:
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:
; to find :
The derivative of is itself.
The result is:
So, the result is:
Now simplify:
The answer is:
x x (-4*sin(4*x) + 4*cos(4*x))*e (sin(4*x) + cos(4*x))*e ----------------------------- + ------------------------ 5 5
x -(7*cos(4*x) + 23*sin(4*x))*e ------------------------------- 5
x (-99*cos(4*x) + 5*sin(4*x))*e ------------------------------ 5