Answers

2014-04-28T18:27:53+05:30
Look at diagram
i have taken R as (0,a) as lies on y axis
slope of AB
 \frac{0-4}{2t-0}= \frac{-2}{t}
the slope of MR is  \frac{t}{2}
 \frac{a-2}{-t}= \frac{t}{2} \\ a= \frac{4-t^2}{2}
so its middle point is
( \frac{a+t}{2} ,\frac{2+0}{2} )=( \frac{4+2t-t^2}{4} ,1)
1 5 1