Another Mechanics Q... haha (1 Viewer)

[mreditor16]

Hi peeps,

some help with this q will be most appreciated.

So, I got a) out by using d/dx (1/2 v^2) = acceleration.

But then when I try b), going nowhere. Tried heaps of ways. OF course, tried the normal way of square-rooting both sides of the result of part a) (well it will be negative root blah, because particle is going towards origin), and then flipping both sides to be dt / dx = blah. BUT the integration gets too messy and integration by substitution doesn’t seem to be a viable option here.

Thanks in advance!

tl;dr – how do you do part b)

 

[Kurosaki]

Would help if you showed us the Q =P

 

[mreditor16]

Sorry, forgot to attach it - http://postimg.org/image/h4s0x2vpv/

Oh also, Kuro, I PMed you with PPs.

 

[Kurosaki]

Try to rationalise the top square root and complete the square on the bottom square root.

 

[mreditor16]

okay i'll try that. brb

 

[mreditor16]

yep thanks kuro - got it out but its very very yucky haha thanks!