Determining initial velocity and instant velocity

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Norfonz
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Homework Statement



The acceleration of a particle is given by ax(t) = 2.90t - 2.06

Q. Find the initial velocity v0x such that the particle will have the same x-coordinate at time t = 4.06 as it had at t = 0.

Homework Equations



vx = v0x + [tex]\int[/tex]axdt evaluated from 0 to t.
x = x0 + [tex]\int[/tex]vxdt evaluated from 0 to t.

This is defined for straight-line motion with varying acceleration, which appears to fit my scenario.

The Attempt at a Solution



vx = v0x + [tex]\int[/tex](2.90t - 2.06)dt evaluated from 0 to t.
vx = v0x + 1.45t2 - 1.03t

x = x0 + [tex]\int[/tex](v0x + 1.45t2 - 1.03t)dt evaluated from 0 to t.
x = x0 + [tex]\int[/tex](1.45t2 - 1.03t)dt + v0x[tex]\int[/tex]dt

x = x0 + v0xt + (1.45t3/3) - (1.03t2/2)

Unfortunately this is as far as I got. I don't understand how to incorporate the values I was given for t. Could someone point me in the right direction please?
 
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Norfonz said:
x = x0 + v0xt + (1.45t3/3) - (1.03t2/2)

Unfortunately this is as far as I got. I don't understand how to incorporate the values I was given for t. Could someone point me in the right direction please?

Well from where, when t=4.06, what is x equal to ? (in terms of v0x and x0)

And when t=0, what is x equal to ? (in terms of v0x and x0)


Then just put those equal to each other and solve for v0x