My name is Sarah and I'm a Calculus student. My question is this:

If f(x)=2x3+4x2-9x+8

and the derivative is f'(x)=6x2+8x-9,

how do I find the critical points if f'(x) is not factorable??

Any help will be greatly appreciated

Hi Sarah,

If you have a quadratic you can always use the general quadratic to solve for the roots, even if you can't factor the expression. If

then the roots are


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