Basic Algebra: Showing E = .5(k/a) Without The Conjugate

[Nusc]

Can someone explain to me why E = .5(k/a)(e^2 - 1)/(1 - e^2) = .5(k/a)

The conjugate won't work, how do I show this?

 

[GeoMike]

Can someone explain to me why E = .5(k/a)(e^2 - 1)/(1 - e^2) = .5(k/a)
The conjugate won't work, how do I show this?

You can factor -1 out of the denominator and then cancel (e^2-1), but that leaves you with E = .5(k/a)(e^2 - 1)/(1 - e^2) = -.5(k/a)

GM

 

[Nusc]

Actually that was what I meant 0.5(k/a), thanks