Mister Exam

Derivative of y=ln(sin3x)

Function f() - derivative -N order at the point
v

The graph:

from to

Piecewise:

The solution

You have entered [src]
log(sin(3*x))
$$\log{\left(\sin{\left(3 x \right)} \right)}$$
d                
--(log(sin(3*x)))
dx               
$$\frac{d}{d x} \log{\left(\sin{\left(3 x \right)} \right)}$$
Detail solution
  1. Let .

  2. The derivative of is .

  3. Then, apply the chain rule. Multiply by :

    1. Let .

    2. The derivative of sine is cosine:

    3. Then, apply the chain rule. Multiply by :

      1. The derivative of a constant times a function is the constant times the derivative of the function.

        1. Apply the power rule: goes to

        So, the result is:

      The result of the chain rule is:

    The result of the chain rule is:

  4. Now simplify:


The answer is:

The graph
The first derivative [src]
3*cos(3*x)
----------
 sin(3*x) 
$$\frac{3 \cos{\left(3 x \right)}}{\sin{\left(3 x \right)}}$$
The second derivative [src]
   /       2     \
   |    cos (3*x)|
-9*|1 + ---------|
   |       2     |
   \    sin (3*x)/
$$- 9 \cdot \left(1 + \frac{\cos^{2}{\left(3 x \right)}}{\sin^{2}{\left(3 x \right)}}\right)$$
The third derivative [src]
   /       2     \         
   |    cos (3*x)|         
54*|1 + ---------|*cos(3*x)
   |       2     |         
   \    sin (3*x)/         
---------------------------
          sin(3*x)         
$$\frac{54 \cdot \left(1 + \frac{\cos^{2}{\left(3 x \right)}}{\sin^{2}{\left(3 x \right)}}\right) \cos{\left(3 x \right)}}{\sin{\left(3 x \right)}}$$
The graph
Derivative of y=ln(sin3x)