Question

Diketahui log 2 = 0,3010; log 3 = 0,4771 dan log 7 = 0,8451 tentukan
a. log 18
b. log 21
c. log 10,5
d. log 1 per 7

Answer 1

Log 18 = log (2.3.3) = log 2 + log 3 + log 9 = 0,301 + 0,4771+0,4771 = 1,2552
log 21 = log 3.7 = log 3 + log 7 = 0,4771 + 0,8451 = 1,3222
log 10,5 = log 21/2 = log 21 - log 2 = 1,3222 - 0,301 = 1,0212
log 1/7 = log 1 - log 7 = 0 - 0,8451 = -0,8451

Answer 2

A. log (2.3.3)
   =log 2+log 3+log 3
=0,310+0,4771+0,4771 = 1,2552
b. log (7.3)
   = log 7 + log 3
   = 0,8451 + 0,4771 = 1,3222
c. log (7.3/2) = log 7+log 3-log 2
   = 0,8541+0,4771-0,3010 = 1,0212
d. log 1 - log 7 = 0 - 0,8451 = 0,8451