Aptitude - Logarithm - Discussion
Discussion Forum : Logarithm - General Questions (Q.No. 6)
6.
| If log10 7 = a, then log10 |  |
1 |  |
is equal to: |
| 70 |
Answer: Option
Explanation:
|
= log10 1 - log10 70 | |||||
| = - log10 (7 x 10) | ||||||
| = - (log10 7 + log10 10) | ||||||
| = - (a + 1). |
Discussion:
33 comments Page 3 of 4.
Subhajit said:
8 years ago
How to -log10(7*10)?
Dev said:
8 years ago
Please explain the second step. I didn't get it.
Anbu said:
8 years ago
Nice. Thank you.
Jesha said:
7 years ago
I can't understand how to solve log 10 (70)?
Please, someone explain me.
Please, someone explain me.
Souradeep said:
7 years ago
How to get this? Please explain.
Tanooja said:
7 years ago
log10(1/70) = -log10(70),
= -log10(7*10),
= -(log10(7) + log10(10)) =-(a+1).
= -log10(7*10),
= -(log10(7) + log10(10)) =-(a+1).
Ibrahim said:
6 years ago
2nd and 4th line is not clear. Please explain those.
Rohit said:
5 years ago
By simply log10(1/70) is explained as:
Log (a/b) formula.
Log a-logb
So,
Log10(1) -log10(70).
In this step log10(1) is 0.
So,
0- log10(70)
We write this step in another way as like.
-log10(7*10).
This step is in the form of;
Log (a*b) =log a+ logb.
So,
-[log10(7) +log10(10) ]
Log10(7) =a
And log10(10) =1.
- (a+1).
Log (a/b) formula.
Log a-logb
So,
Log10(1) -log10(70).
In this step log10(1) is 0.
So,
0- log10(70)
We write this step in another way as like.
-log10(7*10).
This step is in the form of;
Log (a*b) =log a+ logb.
So,
-[log10(7) +log10(10) ]
Log10(7) =a
And log10(10) =1.
- (a+1).
Habib said:
5 years ago
Thanks @Rohit.
(1)
Giri said:
5 years ago
Thank you @Rohit.
(1)
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