Combine logarithmic terms: Use the properties of logarithms to combine the terms in the numerator. limh→0h5log(2+h)−5log(2)=limh→0h5log(22+h)
Apply constant multiple rule: Apply the constant multiple rule in limits to take the constant 5 out of the limit.h→0lim(h5log(22+h))=5×h→0lim(hlog(22+h))
Use derivative definition: Use the definition of the derivative for the function f(x)=log(x) at x=2.limh→0hlog((2+h)/2)=f′(2) where f(x)=log(x)
Calculate derivative: The derivative of log(x) is xln(10)1. So, f′(2)=2ln(10)1.
Multiply by constant: Multiply the derivative by the constant 5 that we factored out earlier.5×f′(2)=5×(2ln(10)1)=2ln(10)5
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