Question

Jika log 2 = x, tentukan log 5!

Answer 1

Log 2 = x
1 / ²log10 = 1/x
1 / ²log(2 x 5) = 1/x
1/ 1 + ²log 5 = 1/x
x = 1 + ²log 5
x-1 = ²log 5
x-1 = log 5 / log2
log 5 = x(x-1)
log 5 = x²-x

bagaimana?

Answer 2

Log 2 = x
log 5 = log (10/2)
        = log 10 - log 2
        = 1 - x

catatan:
log (a/b) = log a - log b
¹⁰log 10 biasa ditulis log 10, bilangan pokok 10 sering tidak ditulis
¹⁰log10 = log 10 = 1