Arun
Last Activity: 6 Years ago
We know that, the semi latus-rectum of a parabola is the harmonic mean between the segments of any focal chord of the parabola.
Given that, b and c are lengths of the segments of any focal chord of the parabola y2=4ax
So, Let l is the length of semi-latus rectum of the parabola.
Then,1/b+1/c=2/l
⇒ l=2bc/(b+c)
Hence, length of latus-rectum=2bc/(b+c)