if log 7 - log 2 + log 16 - 2 log 3 - log 7/ 45 =1 + log n. find n
Answers
Step-by-step explanation:
Given:-
log 7 - log 2 + log 16-2 log 3 - log 7/45 =1 +log n.
To find:-
Find the value of n?
Solution:-
Given that
log 7 - log 2 + log 16-2 log 3 - log 7/45
=1 +log n.
We know that
log (a/b)=log a - log b
=> log7-log2+log16-2log3-(log7-log45)
=1+logn
=>log7-log2+log2^4-2log3-log7+log45
=1+log n
log7-log2+log2^4-2log3-log7+log(3^2×5)
=1+logn
We know that
log(ab)=log a + logb
log7-log2+log2^4-2log3-log7+log3^2
+log5=1+logn
we know that
log a^m = m log a
=>log7-log2+4log2-2log3-log7+2log3+
log5=1+logn
=>(log7-log7)+(-log2+4log2)+(-2log3+2log3) +log5=1+logn
=>0+3log2+0+log5=1+logn
=>3log2+log5=1+logn
=> log 2^3 + log 5 = 1+ log n
=> log 8 + log 5 = 1+log n
=> log (8×5) = 1+ log n
=> log 40 = 1+log n
=> log (10×4) = 1+ log n
=> log 10 + log 4 = 1+ log n
We know that log 10 (10) = 1
=> 1+ log 4 = 1 + log n
On Comparing both sides then
=> n = 4
Answer:-
The value of n for the given problem is 4
Used formulae:-
- log (ab)=log a + log b
- log (a/b)=log a - log b
- log (a^m)=m log a
- log a (a) = 1
- If base of the logarithm of a number is not given then the base is 10 and it is a common logarithm.