I'm studying M3 as one of the three modules for my further maths alevel, and have just started the first chapter. I'm fine with acceleration as a funtion of time, and integrating to find velocity and displacement, and most of acceleration as a function of displacement, but have come stuck on one of the questions:-(adsbygoogle = window.adsbygoogle || []).push({});

A particle p moves along the positive x axis. Its acceleration is (x + 3)ms^-2 when its displacement from the origin O is x meters. Given that initially, when t = 0, the velocity of P is 3ms^-1 in the direction Ox and x = 0. Obtain:-

a) the speed Vms^-1 of P as a funtction of x

b) x as a function of t

I started by trying (1/2)v^2 = INT(X+3)

therefore getting

v^2 = x^2 + 6x + C

where C = 9

therefore:

v^2 = x^2 + 6x + 9

The book's answer however is different, v = x + 3

I dont know how they got that answer, and as for part b) i'm completely lost as i cant figure out how to bring t into the equation.

Any help would be greatly apprectiated,

Thanks,

Bob

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# Homework Help: Mechanics 3 - Further kinematics

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