If log45=aandlog56=bthen log32 is equal to:
Find the product of a and b:
Given log45=a..............................(1)log56=b..............................(2)
ab=log45×log56Multiplyingequation(1)and(2)⇒ab=log5log4×log6log5[∵loga(b)=log(b)log(a)]⇒ab=log6log4⇒ab=log(3×2)log22⇒ab=log3+log22log2[∵log(ab)=log(a)+log(b)]⇒2ab=log2log2+log3log2⇒2ab=1+log23⇒log23=2ab-1⇒log32=12ab-1[∵loga(b)=1logb(a)]
Final answer:
Hence, log3(2) =12ab-1