Integration and initial velocity

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Homework Statement



With what initial velocity must an object be thrown upward (from ground level) to reach a maximum height of 550feet.

Use a(t)= -32ft/sec2 as the acceleration due to gravity. (neglect air resistance)

Homework Equations



Use integration

The Attempt at a Solution



I know that U should first start off by integrating the acceleration in order to get velocity, but I wind up getting:

32x+C= v(t)

I'm not sure how to deal wit the problem from here, does anyone have any suggestions?
 
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What is x?
 
Im pretty sure that x is suppose to be time, because that is the only thing that relates acceleration and velocity
 
I thought t was time as well. So lesson one is to be a bit more precise in your notation.

a(t) = -32 ft/s2, then
v(t) = \int a(t) \, dt
where t is the variable. Integrating a constant over t gives you the constant times t so
v(t)[ft/s] = - 32 t + C

Note the minus sign, which is carried over from a(t) < 0.
C is an integration constant which you need to determine. What condition will you use for this?
How can you see in the v(t) graph or formula that the highest point is reached?
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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