Page 34 - Mathematics Class - XII

MCQs

1. The value of the function log 27 + log 32 is
9 8
a) 7 b) 19 c) 3 d) 4
3 6

2. The value of function log 27 is
log9
a) 2 b) 4 c) 3 d) 3
3 2 4
3. If log (x + 4) + log (x – 4) = 2 log 4, then x is equal to

a) 4 b) 3 2 c) 4 2 d) 3

x
4. If 4 2 2x 1 3 x 1 2 3 x 1 , then x is equal to
2
a) 3 b) 2 c) 5 d) 1
2 3 2
5. If log x + log x + log x = 9, then x is equal to
3
2
3 9 27
a) 3 b) 27 c) 9 d) 81
6. If log (x – x ) – log (x – 1) = 3, then x is equal to
4
3
3 3
a) 3 b) 1 c) 6 d) 9
7. The logarithmic form of (92) = 4 is
1/5
1
1
a) log 4 = b) log 4 = 92 c) log = 3 d) None of these
92 5 1/5 92 5
8. The value of loglog 777 is equal to
7 7
a) 3log 7 b) 1 – 3log 7 c) 1 – 3log 2 d) 7
2 2 7 8
9. If log (x – 1) – log (x+ 1) = 1 then x is equal to
2
4 4
a) 1 b) 2 c) 5 d) 4

x 1 log 5
2 5)
10. If 5 (. 10 , then the value of x is
a) 1 b) log 2 c) log 5 d) 2log 5
10 10 10

3
3
Answers: 1. b) 19 2. d) 3. c) 4 2 4. a) 5. b) 27 6. a) 3
6 4 2
1
7. a) log 4 = 8. c) 1 – 3log 2 9. c) 5 10. d) 2log 5
92 5 7 10

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