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This section draws on the skills learnt the previous parts of the 'Differentiation' series of questions, and some logical thinking about the physics of the problem.

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The steps within the part walk through the process.

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$y=\\var{ct}t-\\var{cts}t^2$

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Firstly, differentiate.

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$\\frac{dy}{dt}=$ [[0]]

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Now use this result and your knowledge of differentiation to find the maximum height of the missile, rounding to the nearest whole number.

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$y=$ [[1]]

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The missile will follow a parabolic curve when height is plotted against time.

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It takes the same amount of time to reach its maximum as it does to fall back down.

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The maximum height will be at the stationary point.

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The stationary point can be found by equating $\\frac{dy}{dt}$ to $0$.

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$\\frac{dy}{dt}=0=$

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Therefore, $t=$

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An unpowered missile is launched vertically from the ground.

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At a time $t$ seconds after the instant of projection, its height, $y$ metres, above the ground is given by the formula

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\\[ y=\\var{ct}t-\\var{cts}t^2. \\]

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Calculate the maximum height reached by the missile.

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Real life problems with differentiation

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