Dear Forum

question

if i am trying to Decide whether f(x)=x^2+2x+4 has a minimum or maximum, and find the value.

would it be miniumum of -1 or maximum of -1 , i am getting stuck.

thanks -ac-

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- Feb 19th 2009, 11:13 AM #1

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- Feb 19th 2009, 11:34 AM #2

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Hi AlgebraicallyChallenged,

$\displaystyle ax^2+bx+c=0$

If a > 0, then you have a minimum value.

If a < 0, then you have a maximum value.

It can be shown that the x-coordinate of the vertex is $\displaystyle -\frac{b}{2a}$. Once you find that, find $\displaystyle f \left(-\frac{b}{2a}\right)$

Your parabola opens upward and has a minimum value of -1. It does not have a maximum.