7log(10/9) - 2log(25/24) +3log(81/80)=কত?
Solution
Correct Answer: Option B
7log(10/9) - 2log(25/24) +3log(81/80)
=7(log10-log9) - 2 (log25-log24) + 3 (log81-log80)
=7(log2.5-log32)-2(log52 - log3.23) + 3 (log34-log24.5)
=7(log2+log5-2log3) - 2(2log5 - log3-3log2) + 3(4log3-4log2-log5)
=7log2+7log5-14log3-4log5+2log3+6log2+12log3-12log2-3log5
=log2