What is the value of 2*log 5 + log 8 – (1/2)*log 4 = ? Assumed all Logs are of base 10

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13 Mar 2020 Logarithm

What is the value of
2*log 5 + log 8 – (1/2)*log 4 = ?
Assumed all Logs are of base 10

OPtion

1) 1
2) 0
3) 10
4) 100
5) 2
6) 20
7) 10^(1/2)
8) 18
9) 24
10) None of these

Solution

2 log 5 + log 8 – ½ log 4

= log (5^2) + log 8 - log (4^(1/2))

= log 25 + log 8 - log 2 = log (25*8)/2

= log 100 =log 10^2 = 2 log 10 = 2 * 1 =2

Correct Option: 5 Best Solution (2)