Points A and B lie on the parabola y=2x2+4x−2 , such that origin is the mid-point of the line segment AB. If ‘l’ be the length of line segment AB, then find the unit digit of l2.___
Open in App
Solution
β=2α2+4α−2 ...(i) −β=2α2−4α−2 ...(ii) (i) & (ii) ⇒4α2−4=0⇒α=±1 Put α=1,β=2+4−2=4 thereforeA(1,4),B(−1,−4) AB2=l2=(√4+64)2=68