LOGARITHMS 4

Evaluate Log100000 +  log 0.01 + log₃243

Solution

= Log100000 +  log 0.0001 + log₃243

= Log10⁵ +  log 10^-4 + log₃3^-5

= 5Log10 +  (-4log 10) + (-5log₃3)    [ since log_aaⁿ  = nlog_aa ]

= (5x1) + (-4x1) + (-5x1)             [ since log_aa = 1 ]

= 5 + (-4) + (-5)

= 5 - 9

= -4

Hence Log100000 +  log 0.01 + log₃243 = -2

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

Evaluate Log1,000,000 +  log 0.01 + log₃729