diketahui 2 log 5 = p. nilai 20 log 125=

2log5 = p
(1/5log2) = 1/p

20log125

20log5^3

3 20log5

3 × (1/(5log20))

3 × (1/(5log2×2×5))

3 × (1/(5log2 + 5log2 + 5log5))

3 × (1/(1/p + 1/p + 1))

3 × (1/(2/p + 1))

3 × (1/(2+p/p))

3 × (1 × p/2+p)

3 × p/2+p

3p
------
2+p