Question

Please tell it urgently

Answer 1

Given :
If L is the perpendicular distance of earth from the sun when it is perpendicular to the major axis.
Case : i
L/r=1-ecosθ
When θ =0; Then r=r1
where r1 is the largest distance from the sun.
∴L/r1=1-e ----- equation [1]
Case : ii
when θ =Π
r=r2
where r2 is the smallest distance from the sun.
so, L/r2=1-ecosΠ
       L/r2     =1+e  ------equation[2]
Adding equation 1 and 2
L/r1 + L/r2 =1-e+1+e=2
∴L[1/r1+1/r2]=2
⇒L[r1+r2/r1r2]=2
⇒L=2 r1r2/r1+r2

So correct option is L= 2r1r2/r1+r2
which is not given the option....

Hope it helps .