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log(cos(x^3))

Derivative of log(cos(x^3))

Function f() - derivative -N order at the point
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The graph:

from to

Piecewise:

The solution

You have entered [src]
   /   / 3\\
log\cos\x //
log(cos(x3))\log{\left(\cos{\left(x^{3} \right)} \right)}
d /   /   / 3\\\
--\log\cos\x ///
dx              
ddxlog(cos(x3))\frac{d}{d x} \log{\left(\cos{\left(x^{3} \right)} \right)}
Detail solution
  1. Let u=cos(x3)u = \cos{\left(x^{3} \right)}.

  2. The derivative of log(u)\log{\left(u \right)} is 1u\frac{1}{u}.

  3. Then, apply the chain rule. Multiply by ddxcos(x3)\frac{d}{d x} \cos{\left(x^{3} \right)}:

    1. Let u=x3u = x^{3}.

    2. The derivative of cosine is negative sine:

      dducos(u)=sin(u)\frac{d}{d u} \cos{\left(u \right)} = - \sin{\left(u \right)}

    3. Then, apply the chain rule. Multiply by ddxx3\frac{d}{d x} x^{3}:

      1. Apply the power rule: x3x^{3} goes to 3x23 x^{2}

      The result of the chain rule is:

      3x2sin(x3)- 3 x^{2} \sin{\left(x^{3} \right)}

    The result of the chain rule is:

    3x2sin(x3)cos(x3)- \frac{3 x^{2} \sin{\left(x^{3} \right)}}{\cos{\left(x^{3} \right)}}

  4. Now simplify:

    3x2tan(x3)- 3 x^{2} \tan{\left(x^{3} \right)}


The answer is:

3x2tan(x3)- 3 x^{2} \tan{\left(x^{3} \right)}

The graph
02468-8-6-4-2-1010-50005000
The first derivative [src]
    2    / 3\
-3*x *sin\x /
-------------
      / 3\   
   cos\x /   
3x2sin(x3)cos(x3)- \frac{3 x^{2} \sin{\left(x^{3} \right)}}{\cos{\left(x^{3} \right)}}
The second derivative [src]
     /            / 3\      3    2/ 3\\
     |   3   2*sin\x /   3*x *sin \x /|
-3*x*|3*x  + --------- + -------------|
     |           / 3\          2/ 3\  |
     \        cos\x /       cos \x /  /
3x(3x3sin2(x3)cos2(x3)+3x3+2sin(x3)cos(x3))- 3 x \left(\frac{3 x^{3} \sin^{2}{\left(x^{3} \right)}}{\cos^{2}{\left(x^{3} \right)}} + 3 x^{3} + \frac{2 \sin{\left(x^{3} \right)}}{\cos{\left(x^{3} \right)}}\right)
The third derivative [src]
   /          / 3\      3    2/ 3\      6    / 3\      6    3/ 3\\
   |   3   sin\x /   9*x *sin \x /   9*x *sin\x /   9*x *sin \x /|
-6*|9*x  + ------- + ------------- + ------------ + -------------|
   |          / 3\         2/ 3\          / 3\            3/ 3\  |
   \       cos\x /      cos \x /       cos\x /         cos \x /  /
6(9x6sin3(x3)cos3(x3)+9x6sin(x3)cos(x3)+9x3sin2(x3)cos2(x3)+9x3+sin(x3)cos(x3))- 6 \cdot \left(\frac{9 x^{6} \sin^{3}{\left(x^{3} \right)}}{\cos^{3}{\left(x^{3} \right)}} + \frac{9 x^{6} \sin{\left(x^{3} \right)}}{\cos{\left(x^{3} \right)}} + \frac{9 x^{3} \sin^{2}{\left(x^{3} \right)}}{\cos^{2}{\left(x^{3} \right)}} + 9 x^{3} + \frac{\sin{\left(x^{3} \right)}}{\cos{\left(x^{3} \right)}}\right)
The graph
Derivative of log(cos(x^3))