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Quick Applied Maths question!

Adventure · 2008-06-18 21:41:26

The displacement x of a particle from a fixed point o at a time t is given by x = 8cos 6t + 15sin 6t Find when x = 0 for the first time. ( amplitude = 7) Anyone have any ideas?:confused:

18-06-2008 9:41pm

#1

Adventure

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The displacement x of a particle from a fixed point o at a time t is given by

x = 8cos 6t + 15sin 6t

Find when x = 0 for the first time. ( amplitude = 7)

Anyone have any ideas?

0

Comments

#2 18-06-2008 10:29pm

postalservice

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What question is this, as in what topic?
Its scares me!

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#3 18-06-2008 10:32pm

ZorbaTehZ

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I'll give it a shot...
8Cos 6t + 15Sin 6t = 0
Sin 6t/Cos 6t = -8/15
Tan 6t = -8/15
t = -0.082
So after pi/2, it'll be back at 0 displacement from o, ie t=1.489.

Edit: Actully I think you should be adding pi to it so that would make it t=3.0599

0
#4 18-06-2008 10:34pm

tabouli

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Simple harmonic motion, is it? :?

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