# CBSE class 12th maths answers key: term 1 Board Exam Question Paper and Answers Key 2021-22

Read all CBSE class 12th maths answer key 2021 – 2022 with question paper.

• MATHEMATICS सत्र – I / Term – I
• निर्धारित समय – 90 मिनट  Time allowed: 90 Minutes.
• अधिकतम अंक : 40 Maximum Marks : 40

## CBSE class 12 maths answers key: Board Exam Question Paper and Answers Key 2021-22 Table

Q1: 1 . Differential of log [ log ( log x5 ) ] w.r.t. x is

5 x log ( r ) log ( log ) ( c ) 5×4 log ( ) log ( log x³ ) ( b ) ( d ) x log ( logº ) 5×4 log log ( log x³ )

### Q2: The number of all possible matrices of order 2 x 3 with each entry 1 or 2 is

1. 16
2. 6
3. 64
4. 24

(C) 64 is the correct answer.

### Q3: A function f : R → R is defined as f(x) = x3 + 1. Then the function has

1. (a) no minimum value
2. (b) no maximum value
3. (c) both maximum and minimum value
4. (d) neither maximum value nor minimum value

(d) neither maximum value nor minimum value is the correct answer.

### Q4: If siny=xcos(a+y), then dx/dy is • (a) (±5, 0)
• (b) (0, ±5)
• (c) (0, ±3)
• (d) (±3, 0)

• (a) 0
• (b) 2
• (c) 3
• (d) 1

### Q9: If a matrix A is both symmetric and skew symmetric , then A is necessarily

• ( a ) Diagonal matrix
• (b) Zero square matrix
• (c) Square matrix
• ( d ) Identity matrix

### Q10: Lat set X = (1. 2, 3) and a relation R is defined in X as : R = ((1, 3), (2, 2), (3. 2)), then minimum ordered pairs which ahould be added in relation R to make it reflexive and symmetric are

• (a) {(1. 1). (2. 3). (1. 2)}
• (b) {(3, 3), (3. 1). 0, 2)}
• (c) {(1. 1), (3. 3). (3. 1). (2,3)}
• (d) {(1. 1). (3, 3), (3. 1), (1. 2)}

Answer: (c) {(1. 1), (3. 3). (3. 1). (2,3)}. 