Apply the quotient rule, which is:
dxdg(x)f(x)=g2(x)−f(x)dxdg(x)+g(x)dxdf(x)
f(x)=3(4x+5)log(x) and g(x)=log(2).
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)=4x+5; to find dxdf(x):
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Differentiate 4x+5 term by term:
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The derivative of the constant 5 is zero.
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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
The result is: 4
g(x)=log(x); to find dxdg(x):
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The derivative of log(x) is x1.
The result is: 4log(x)+x4x+5
So, the result is: 12log(x)+x3(4x+5)
To find dxdg(x):
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The derivative of the constant log(2) is zero.
Now plug in to the quotient rule:
log(2)12log(x)+x3(4x+5)