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Find the coordinates of the critical point of the function below and state whether it is a maximum or a minimum point. Give your answers to $2$ decimal places where necessary.

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$F(x)=\\simplify {{f}x^2+{g}x+{h}}$

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Firstly, find the first and second derivatives:

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$F'(x)=$ [[2]]

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$F''(x)=$ [[3]]

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Secondly, find $x$ such that $F'(x)=0$

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critical point $=$ [[0]]

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value of $F$ at the critical point $=$ [[1]]

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The critical point is a point of  [[4]]

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maximum

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Parts A and B

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Here, the question takes you throught the stages needed to find the solution. The reason we differentiate is that the derivative of a function tells us its gradient at a given point, and we want to find where the function has gradient zero because when the gradient is zero we either have a maximum or a minimum point.

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Part C

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The first part of this question is similar to parts A and B. The tricky bit is the second part! You need to work out the value of $t$ that produces the maximum piont but that is not the final answer - you need to use that value of $t$ to find the maximum height, which you do by substituting $t$ into the original function to find $y$.

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Is the stationary point a maximum?

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