This document contains 15 problems related to logarithms and their properties. It includes the name of the author, their contact information, and the date. For each problem, the author has written the problem statement and solution. The problems cover topics like simplifying logarithmic expressions, determining unknown variables from logarithmic equations, and finding integral parts of logarithms.
3. If logxa = logya , both x,y > a and
a is natural number then which of
the following is necessarily true?
1) x is always equal to y
2) x is never equal to y
3) x need not be equal to y
logxa = logya implies xt = yt = a
When t = 0, x need not be equal to y
When t = 1, x should be equal to y
When t = 2, x need not be equal to y.
In general x need not be equal to y.
12-Jun-15
C.S.VEERARAGAVAN 9894834264
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II
4. If log36 + log312 = log3m, m =
?
1) 9 2) 18 3) 3 4)
72
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III
10. If 2𝑙𝑜𝑔232
= 𝑘, what is the value
of k?
1) 81 2) 27 3) 9 4)
243
2𝑙𝑜𝑔232
= 𝑘
Since 𝑎 𝑙𝑜𝑔 𝑎 𝑁
= N
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IX
11. If 4 = log3p, p = ?
1) 81 2) 27 3) 9 4)
243
34 = p
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X
13. If logax = logay , where a ≠ 1,
both x,y are positive then which
of the following is necessarily
true?
1) x is always equal to y
2) x is never equal to y
3) x need not be equal to y
12-Jun-15
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XII
14. If log169 = k log23, then k = ?
1) 1 2) 2 3)
1
2
4)
1
4
𝑙𝑜𝑔169 =
𝑙𝑜𝑔9
𝑙𝑜𝑔16
2𝑙𝑜𝑔3
2𝑙𝑜𝑔4
𝑙𝑜𝑔23
𝑙𝑜𝑔24
1
2
𝑙𝑜𝑔23
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XIII
15. What is the integral part of
log210000?
1) 11 2) 12 3) 13
4) 14
10000 lies between 213 and 214.
Hence log210000 lies between 13 & 14
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C.S.VEERARAGAVAN 9894834264
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XIV
16. If N is a 20-digit number, what is
the integral part of log10N?
1) 118 2) 19 3) 120 4)
21
Any 20 digit number lies between 1019
and 1020.
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XV