Question

Diketahui log2=0,3010 ; log3=0,4771 ; log7=0,8451 tentukan:
A. Log18
B. Log21
C. Log10,5
D. Log1/7

Answer 1

A) log18 = log(2x9) = log2 + log3² = log2 + 2log3 = 0,3010 + 2(0,4771) = 0,3010 + 0,9542

b) log21 = log3 + log7 = 0,3010 + 0,8451 = 1,1461

c) log10,5 = log(21/2) = log21 - log2 = log3 + log7 - log2 = 0,4771 + 0,8451 - 0,3010 = 1,0212

d) log(1/7) = log1 - log 7 = 0 - 0,8451 = -0,8451