# At what value of x is g(x) increasing most rapidly?

Let f(x) = 5 + 6x + 12x^2 - 2x^3 - x^4 and let g(x) = f(x) for any real number x. At what value of x is g(x) increasing most rapidly?

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#### Solution Preview

f(x)=5+6x+12x^2-2x^3-x^4.

Then f'(x)=6+24x-6x^2-4x^3

To find the ...

#### Solution Summary

A double derivative is used to find the value of x where g(x) is increasing most rapidly.

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