ParabolaEasy
Question
The equation of lactus rectum of a parabola is x + y = 8 and the equation of the tangent at the vertex is x + y = 12, then length of L.R. is :-
Options
A.4√2
B.2√2
C.8
D.8√2
Solution
Since, the equation of latus rectum and equation of tangent both are parallel and they lie in the same side of the origin
∴ a =
= 2√2)
∴ Length of latus rectum = 4a = 4(2√2)
= 8 √2
∴ a =
= 2√2)∴ Length of latus rectum = 4a = 4(2√2)
= 8 √2
Create a free account to view solution
View Solution FreeMore Parabola Questions
If two distinct chords of parabola $y^{2} = 4ax(a > 0)$ passing through $(a,2a)$ are bisected by the line $x + y = 1$...Locus of the intersection of the tangents at the ends of the normal chords of the parabola y2 = 4ax is -...$ABCD$ and $EFGC$ are squares and the curve $y = k\sqrt{x}$ passes through the origin $D$ and the points $B$ and $F$. Th...For the parabola $y^{2} + 4x - 4y = 4$, the straight line $x - y + 3 = 0$ is :...PQ is a normal chord of the parabola y2 = 4ax at P, A being the vertex of the parabola. Through P a line is drawn parall...