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## Homework Statement

A planet has an eccentricity of 0.006800 and a semimajor axis of 0.7233 AU, find the ratio of ortibal speed at perihelion to that at aphelion.

## Homework Equations

d=e x a

L=mvrsin[tex]\theta[/tex]

## The Attempt at a Solution

I plugged in and solved for the distance between the foci (0.004918)

and then set the angular momentum constants equal to each other:

m v(p) rmin sin[tex]\theta[/tex]=m v(a) rmax sin[tex]\theta[/tex]

the masses and sin[tex]\theta[/tex] cancel out, so

v(p) x r min = v(a) x r max

and so the ratio is:

v(p) / v(a) = r max / r min

r max is the semimajor axis, and r min is the semimajor axis minus the d as found above:

So, it should be .7233/.718382 which gives me 1.00685, but this was incorrect according to my online homework, could you tell me what I did wrong?