(Mathematics) NDA/NA SOLVED PAPER 2024 – I (51 to 100)Total Questions: 501. If (a, b) is the centre and c is the radius of the circle x² + y² + 2x + 6y + 1 = 0 then what is the value of a²+ b² + c²?(a) 19(b) 18(c) 17(d) 11Correct Answer: (a) 19Solution:2. If (1, - 1, 2) and (2, 1, -1) are the end points of a diameter of a sphere x² + y²+ z² + 2ux + 2vy + 2wz - 1 = 0 then what is u + v + w equal to?(a) -2(b) -1(c) 1(d) 2Correct Answer: (a) -2Solution:3. The number of points represented by the equation x = 5 on the xy-plane is(a) Zero(b) One(c) Two(d) infinitely manyCorrect Answer: (d) infinitely manySolution:4. If are the directions cosines of a normal to the plane 2x - 3y + 6z + 4 = 0 then what is the value of 49 (7l² + m² - n²)?(a) 0(b) 1(c) 3(d) 71Correct Answer: (b) 1Solution:5. A line through (1, -1, 2) with directions ratios meets the plane x + 2y + 3z = 18. What is the point of intersection of line and plane?(a) (4, 4, 1)(b) (2, 4, 1)(c) (4, 1, 4)(d) (3, 4, 7)Correct Answer: (c) (4, 1, 4)Solution:6. If p is the perpendicular distance from origin to the plane passing through (1, 0, 0), (0, 1, 0) and (0, 0, 1), then what is 3p² equal to ?(a) 4(b) 3(c) 2(d) 1Correct Answer: (d) 1Solution:7. If the directions cosines of a line are connected by relation l + 2m + n = 0, 2l - 2m + 3n = 0, then what is the value of l²+ m²- n²?(a) 1/101(b) 29/101(c) 41/101(d) 92/101Correct Answer: (b) 29/101Solution:8. If a variable line passes through the point of intersection of the lines x + 2y - 1 = 0 and 2x - y - 1 = 0 and meets the coordinate axes in A and B, then what is the locus of the mid-point of AB?(a) 3x + y = 10xy(b) x + 3y = 10xy(c) 3x + y = 10(d) x + 3y = 10Correct Answer: (b) x + 3y = 10xySolution:(b)9. What is the equation to the straight line passing through the point (- sin θ, cos θ) and perpendicular to the line x cos θ + y sin θ =9?(a) x sin θ - y cos θ - 1 = 0(b) x sin θ - y cos θ + 1 = 0(c) x sin θ - y cos θ = 0(d) x cos θ - y sin θ + 1 = 0Correct Answer: (b) x sin θ - y cos θ + 1 = 0Solution:10. Two points P and Q lie on line y = 2x + 3 These two points P and Q are at a distance 2 units from another point R(1, 5). What are the coordinates of the points P and Q?(a)(b)(c)(d)Correct Answer: (a)Solution:Submit Quiz12345Next »