Let one end of a focal chord of the parabola y2=16x be (16, 16). If P(α,β) divides this focal chord internally in the ratio 5:2, then the minimum value of α+β is equal to :
(A)22
(B)7✓ Correct
(C)5
(D)16
Answer: (B)
Solution
For y2=16x, a=4 and a point is (4t2,8t); the end (16,16) corresponds to t=2. The other end of a focal chord has parameter −t1=−21, i.e. (1,−4). Dividing the join of (16,16) and (1,−4) internally in the ratio 5:2 from the first end gives P=(75(1)+2(16),75(−4)+2(16))=(737,712) with α+β=7; dividing from the other end gives (782,772) with α+β=22. The minimum value of α+β is 7.Case 1Case 2
JEE Main · 2026 · 21 Jan 2026 · Shift 2 · Single correct option