Diketahui 2 log3 = a dan 3 log5 = b . Berapakah nilai 25 log81 x 2 log 25 ?

2log3 = a
3log5 = b
2log3×3log5 = ab
2log5 = ab

25log81 × 2log25

5^2log3^4 × 2log5^2

4
-- 5log3 × 2 2log5
2

2 5log3 × 2 2log5

1
2 --- × 2 ab
b

2 2 ab^2
--- × -----------
b b