2log 3 = a dan ³log 5 = b tentukan 8log 625

2log 3 × 3log 5 = 2log 5 = ab

8log625 = 2^3log5^4 = 3/4 × 2log5
= 3/4 ×ab

2log3 = a.==» log3/log2 = a.
3log5 = b, ==» log5/log3 = b.
8log625 = log625/log8
= log 5^4 / log 2^3
= 4.log 5 / 3. log 2 (ganti bilangan pokok 3)
= 4, 3log 5 / 3. 3log2
= 4.b / 3. 1/a
= 4b / (3/a)
= (4ab/3)