Mathematics (NDA/NA SOLVED PAPER 2019 (I) (01 to 50)Total Questions: 5041. Simplify the question?(a) 0(b) π/6(c) π/4(d) π/2Correct Answer: (c) π/4Solution:42. If cos A = 3/4, then what is the value of sin(A/2) sin(3A/2)?(a) 5/8(b) 5/16(c) 5/24(d) 7/32Correct Answer: (b) 5/16Solution:43. What is the value of tan75° + cot 75°?(a) 2(b) 4(c) 2√3(d) 4√3Correct Answer: (b) 4Solution:44. What is the value of cos 46° cos 47° cos 48° cos 49° cos 50°..........cos 135°?(a) −1(b) 0(c) 1(d) Greater than 1Correct Answer: (b) 0Solution:45. If sin2θ = cos3θ, where 0<θ<π/2, then what is sinθ equal to?(a)(b)(c)(d)Correct Answer: (b)Solution:46. If the roots of the equation x² + px + q = 0 are tan19° and tan26°, then which one of the following is correct?(a) q - p = 1(b) p - q = 1(c) p + q = 2(d) p + q = 3Correct Answer: (a) q - p = 1Solution:47. What is the fourth term of an AP ofn terms whose sum is n(n + 1)?(a) 6(b) 8(c) 12(d) 20Correct Answer: (b) 8Solution:48. What is − sec²α sec²β equal to?(a) 0(b) 1(c) 2(d) 4Correct Answer: (a) 0Solution:49. If p = cosecθ - cotθ and q = (cosecθ + cotθ)⁻¹, then which one of the following is correct?(a) pq = 1(b) p = q(c) p + q = 1(d) p + q = 0Correct Answer: (b) p = qSolution:50. If the angles of a triangle ABC are in the ratio 1 : 2 : 3, then the corresponding sides are in the ratio:(a) 1 : 2 : 3(b) 3 : 2 : 1(c) 1 : √3 : 2(d) 1 : √3 : √2Correct Answer: (c) 1 : √3 : 2Solution:Submit Quiz« Previous12345