take alook....

we have
<br />
v^2=mu(2/r - 1/a)<br />
and
<br />
r= a(1-e cosE)<br />
so
<br />
v=(mu)^1/2 (2/{a(1-e cosE)}  -  1/a)^1/2<br />

<br />
v=(mu)^1/2 ({2-1+e cosE}/{a(1-e cosE)})^1/2<br />

<br />
v=(mu/a)^{1/2} \left(\frac{1+e\ \cos(E)}{1-e\ \cos(E)}\right)^{1/2}<br />

is it true