Apply the quotient rule, which is:
dxdg(x)f(x)=g2(x)−f(x)dxdg(x)+g(x)dxdf(x)
f(x)=sin(4x−2) and g(x)=cos(4x−2).
To find dxdf(x):
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Let u=4x−2.
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The derivative of sine is cosine:
dudsin(u)=cos(u)
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Then, apply the chain rule. Multiply by dxd(4x−2):
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Differentiate 4x−2 term by term:
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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 power rule: x goes to 1
So, the result is: 4
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The derivative of the constant −2 is zero.
The result is: 4
The result of the chain rule is:
4cos(4x−2)
To find dxdg(x):
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Let u=4x−2.
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The derivative of cosine is negative sine:
dudcos(u)=−sin(u)
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Then, apply the chain rule. Multiply by dxd(4x−2):
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Differentiate 4x−2 term by term:
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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 power rule: x goes to 1
So, the result is: 4
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The derivative of the constant −2 is zero.
The result is: 4
The result of the chain rule is:
−4sin(4x−2)
Now plug in to the quotient rule:
cos2(4x−2)4sin2(4x−2)+4cos2(4x−2)