I am asked in a question to show that the friedman with k<0 equation can be solved by substituing(adsbygoogle = window.adsbygoogle || []).push({});

a= b(1-cos(theta)) and t = c(theta- sin(theta).

a is scale factor,

t is time

b,c are constants

Can anyone outline the general procedure to go about solving this.

I've tried substituting da/dt using the chain rule to obtain da/d(theta)*d(theta)/dt, but this leads to an uneliminated cos terms...

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# Homework Help: Cosmology Problem, Friedman equation

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