Final JEE - Main Exam September, 2020/02-09-2020/Evening Session
FINAL JEE–MAIN EXAMINATION – SEPTEMBER, 2020 (Held On Wednesday 02nd SEPTEMBER, 2020)
TEST PAPER WITH SOLUTION
MATHEMATICS 1.
TIME : 3 PM to 6 PM
The area (in sq. units) of an equilateral triangle
1
inscribed in the parabola y2 = 8x, with one of
n
its vertices on the vertex of this parabola, is : (1) 64 3
(2) 256 3
(3) 192 3
(4) 128 3
2
Sol.
3
Official Ans. by NTA (3)
4
(2t2,4t) A y2=8x
Number of blue lines = Number of sides = n
Sol.
O (0,0)
30°
EN
Number of red lines = number of diagonals
nC
B 4t 2 Þ t =2 3 2 = 2t t
3.
AB = 8t = 16 3
Area = 256.3·
Let n > 2 be an integer. Suppose that there are
A
2.
3 = 192 3 4
n Metro stations in a city located along a circular path. Each pair of stations is connected by a straight track only. Further, each pair of nearest stations is connected by blue line, whereas all remaining pairs of stations are
(1) 199
(2) 101
(3) 201
(4) 200
n(n - 1) - n = 99 n 2
If the equation cos4q+sin4q + l = 0 has real solutions for q, then l lies in the interval : é 3 5ù (1) ê - , - ú ë 2 4û
æ 1 1ù (2) ç - , - ú è 2 4û
æ 5 ö (3) ç - , -1 ÷ 4 è ø
1ù é (4) ê -1, - ú 2û ë
Official Ans. by NTA (4) Sol. l = – (sin4q + cos4q) l = – (sin2q + cos2q)2 – 2sin2qcos2q
connected by red line. If the number of red lines is 99 times the number of blue lines, then the value of n is :-
– n = 99 n Þ
n -1 - 1 = 99 Þ n = 201 2
LL
tan 30° =
2
= nC2 – n
l=
sin 2 2q -1 2
sin 2 2q é 1 ù Î ê0, ú 2 ë 2û
Official Ans. by NTA (3)
1ù é l Î ê-1, - ú 2û ë 1