Thanks, I think I understand it, I have worked out H(a) too. I'm just stuck on how to make ρM = ρDE. As well as the formulae that associates the scale factor with z.
Thanks
Regards
Phil1093
Here is the problem link picture http://i.imgur.com/0BtcXJk.png
I know that omega=density/critical density
so I know I can find the value of all of those.
DE is dark energy and M is matter (I'm pretty sure).
I assume I have to sub that formula into equation 1, and then rearrange it to create a...