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In this question, i want to find the position and velocity of an object moving along a straight line with the given acceleration, initial velocity, and initial position.
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Here my a of t is the cosine of 2t.
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V of 0 is equal to 5, and s of 0 is equal to 7.
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So, first i've got to go from my acceleration back to my velocity.
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Velocity is found by integrating my acceleration function.
00:28
So it's the integral of the cosine of 2t dt.
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My antiderivative of the cosine of 2t is the sine of 2t over 2.
00:40
1 half sine of 2t plus c.
00:45
Now i'm going to use the fact that v of 0 is equal to 5.
00:49
So v of 0 is equal to 1 half sine of 0 plus c.
00:56
Since v of 0 is 5, i'm getting 5 equals 0 plus c, so that c itself is 5.
01:05
And this gives us v of t, which is 1 half sine of 2t plus 5.
01:18
Now i want my position...