Maths MCQs for AD (ASF)
Q11. Rank of identity matrix of order n is:
- A. 1
- B. n
- C. 0
- D. Undefined
Answer: B
An identity matrix has full rank equal to its order n.
Q12. Integral of 1/x dx equals:
- A. ln x + C
- B. x + C
- C. 1/x + C
- D. eˣ + C
Answer: A
∫1/x dx = ln|x| + C, the natural logarithm of x.
Q13. Distance between points (0,0) and (3,4):
Answer: A
Distance formula: √[(3−0)² + (4−0)²] = √(9+16) = 5.
Q14. If Aᵀ = −A, matrix A is:
- A. Symmetric
- B. Skew-symmetric
- C. Diagonal
- D. Identity
Answer: B
A matrix is skew-symmetric if its transpose equals negative of itself.
Q15. e⁰ equals:
- A. 0
- B. 1
- C. e
- D. Undefined
Answer: B
Any number to the power 0 equals 1, so e⁰ = 1.
Q16. The modulus of complex number 3+4i:
Answer: A
Modulus = √(3² + 4²) = √25 = 5.
Q17. If probability of event A is 0.3, then P(not A):
- A. 0.7
- B. 0.3
- C. 1.3
- D. 0
Answer: A
P(not A) = 1 − P(A) = 1 − 0.3 = 0.7.
Q18. cos²x + sin²x equals:
Answer: B
Fundamental trigonometric identity: cos²x + sin²x = 1.
Q19. The equation of circle with radius r and center origin:
- A. x²+y²=r²
- B. x²−y²=r²
- C. x+y=r
- D. xy=r²
Answer: A
Standard circle formula with center at origin: x² + y² = r².
Q20. If arithmetic mean of 2 and 6 is required:
Answer: B
Arithmetic mean = (2+6)/2 = 4.
