Help for Dynamics! Continuous Motion

1. Jul 30, 2011

JamieShumJr

Can someone tell me how to obtain the figure in red circle? I've trying out on my own but can't get that.

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2. Jul 30, 2011

tiny-tim

Welcome to PF!

Hi JamieShumJr! Welcome to PF!
You're asking why is ∫ (0.8t + A)-1/2 dt = (2/0.8)(0.8t + A)1/2

apply the https://www.physicsforums.com/library.php?do=view_item&itemid=353" twice

if you differentiate the RHS, you get an extra 0.8 from the t, and an extra 1/2 from the power, = (0.8/2)

Last edited by a moderator: Apr 26, 2017
3. Jul 30, 2011

JamieShumJr

Re: Welcome to PF!

Thanks a lot! I neglected the 0.8 during the integration. Got it already. Forgotten the basic rule of integration.

Last edited by a moderator: Apr 26, 2017
4. May 19, 2013

mintz

may i know from same question as above shown, how to get the -1/60 at the end there?

5. May 19, 2013

tiny-tim

welcome to pf!

hi mintz! welcome to pf!
the $|^t_0$ at the end of the previous line means you have to evaluate it at t and at 0, and subtract

6. May 19, 2013

mintz

oh~okie~thanks! i made mistake that evaluate at 0 whole things became 0~
thanks anyway!=D

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