The rate of change of a given function is given by f'(x)=dy/dx
given that the function is:
f(x)=12+2^(-2x)
f'(x)=2*(-2)e^(-2x)
f'(x)=-4e^(-2x)
the relative rate of change will be the ratio of the derivative to the original function:
f'(x)/f(x)
=(12+2^(-2x))/(-4e^(-2x))
The answer is twenty-five cents.
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