Can You Solve These Conservation of Energy Equations?

[blayman5]

I have to prove in a conservation of energy question

T-W =(mv^2)/L

mgL(1-cosO)=(mv^2)/2

mg=W

T=W(3-2Cos0)

How could I go about starting this?

 

[CompuChip]

Assuming you can use the first three equations, use the first one to isolate T, then use the second one to get rid of the (mv^2) and finally replace the third one wherever possible. It should work out... just try it and post how far you get.

 

[blayman5]

I got it:

T-W =(mv^2)/L
mgL(1-cosO)=(mv^2)/2

T=(mv^2)/L+W
mv^2=2mgL(1-cosO)
T=(2mgL(1-cosO))/L+W
T=(2W(1-cosO))/+W
T=2W-2WcosO+W
T=3W-2WcosO
T=W(3-2cosO)

Thanks