SOLUTION: find the minimum and the maximum points of a functions f(x)= 6x^3+7x^2-3x+1

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Question 1121340: find the minimum and the maximum points of a functions
f(x)= 6x^3+7x^2-3x+1
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
Take the derivative and set it equal to 0.
18x^2+14x-3=0
x=(1/36)(-14+/- sqrt (196+216); sqrt 412=20.3
x= +0.175 and -0.95
f(x)=0.72 and 5.02
at x=0 f(x)=1, so x=0.175 must be a local minimum
second derivate at that value (36x+14) is also positive, consistent with that
x=-0.95 is a local maximum, since second derivative at -0.95 is negative.
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