Apply the quotient rule, which is:
dxdg(x)f(x)=g2(x)−f(x)dxdg(x)+g(x)dxdf(x)
f(x)=3x2log(sin(x)) and g(x)=12.
To find dxdf(x):
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The derivative of a constant times a function is the constant times the derivative of the function.
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Apply the product rule:
dxdf(x)g(x)=f(x)dxdg(x)+g(x)dxdf(x)
f(x)=x2; to find dxdf(x):
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Apply the power rule: x2 goes to 2x
g(x)=log(sin(x)); to find dxdg(x):
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Let u=sin(x).
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The derivative of log(u) is u1.
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Then, apply the chain rule. Multiply by dxdsin(x):
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The derivative of sine is cosine:
dxdsin(x)=cos(x)
The result of the chain rule is:
sin(x)cos(x)
The result is: sin(x)x2cos(x)+2xlog(sin(x))
So, the result is: sin(x)3x2cos(x)+6xlog(sin(x))
To find dxdg(x):
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The derivative of the constant 12 is zero.
Now plug in to the quotient rule:
4sin(x)x2cos(x)+2xlog(sin(x))