LOGARITHMS 4

Evaluate Log10,000,000 +  log 0.00001 + log₃243

Solution

= Log10,000,000  +  log 0.001 + log₃243

= Log10⁷ +  log 10^-5 + log₃3⁵

= 7Log10 +  (-5log 10) + (5log₃3)    [since log_aaⁿ  = nlog_aa]

= (7x1) + (-5x1) + (5x1)             [since log_aa = 1]

= 7 + (-5) + (5)

= 7

Hence Log10,000,000 +  log 0.00001 + log₃243 = 7

TRY THIS...............................

Evaluate Log100,000,000 +  log 0.01 + log₃2187