Mathematics NDA/NA SOLVED PAPER 2019 (II) (01 to 50)Total Questions: 501. If both p and q belong to the set {1,2,3,4}, then how many equations of the form px² + qx + 1 = 0 will have real roots?(a) 12(b) 10(c) 7(d) 6Correct Answer: (d) 6Solution:2. What is the value of 1 - 2 + 3 - 4 + 5 -.........+101?(a) 51(b) 55(c) 110(d) 111Correct Answer: (a) 51Solution:3. If A B, and C are subsets of a given set, then which one of the following relations is not correct?(a) A ∪ (A ∩ B) = A ∪ B(b) A ∩ (A ∪ B) = A(c) (A ∩ B) ∪ C = (A ∪ C) ∩ (B ∪ C)(d) (A ∪ B) ∩ C = (A ∩ C) ∪ (B ∩ C)Correct Answer: (a) A ∪ (A ∩ B) = A ∪ BSolution:4. If the sum of first n terms of a series is (n + 12), then what is its third term?(a) 1(b) 2(c) 3(d) 4Correct Answer: (a) 1Solution:5. What is the value of k for which the sum of the squares of the roots of 2x² - 2(K - 2)x - (K + 1) = 0 is minimum?(a) − 1(b) 1(c) 3/2(d) 2Correct Answer: (c) 3/2Solution:6. If the roots of the equation a(b - c)x² + b(c - a)x + c(a - b) = 0 are equal, then which one of the following is correct?(a) a b, and c are in AP(b) a b, and c are in GP(c) a b, and c are in HP(d) a b, and c do not follow any regular patternCorrect Answer: (c) a b, and c are in HPSolution:7. If |x² - 3x + 2| >x² - 3x + 2, then which one of the following is correct?(a) x ≤ 1 or x ≥ 2 (b) 1 ≤ x ≤ 2 (c) 1< x < 2 (d) x is any real value except 3 and 4(a)(b)(c)(d)Correct Answer: (c)Solution:8. A geometric progression (GP) consists of 200 terms. If the sum of odd terms of the GP is m, and the sum of even terms of the GP is n, then what is its common ratio?(a) m / n(b) n / m(c) m + (n / m)(d) n + ( m /n)Correct Answer: (b) n / mSolution:9. If a set A contains 3 elements and another set B contains 6 elements, then what is the minimum number of elements that (A ∪ B) can have?(a) 3(b) 6(c) 8(d) 9Correct Answer: (b) 6Solution:10. What is the number of diagonals of an octagon?(a) 48(b) 40(c) 28(d) 20Correct Answer: (d) 20Solution:Submit Quiz12345Next »