Logarithm Worksheet Express the equation in exponential form
Solution
1. log5 25 = 2, then 25 = 52 ; 2. log8 2 = 1/3, then 2 = 81/3
3. 53 = 125, then 3 = log5 125 ; 4. 8-1 = 1/8, then -1= log8 (1/8)
5. (a) log6 36=log6 62 =2 log6 6 =2;(b) log9 81 = log9 92 =2log 9 9 =2 ;(c) log7 710= 10log7 7 = 10
6. (a) log3 (1/27)= log3( 3-3) = -3log3 3 = -3; (b) log1010 = log10(10)1/2 = 1/2 log10 10 = 1/2; (c) log5 0.2=log5 (1/5) = log5 5-1=-1log5 5 = -1
7. 2log237 = 37 ( if 2log237 = a, then on taking log to the base 2, we have ( log2 37)(log2 2) = log2 a or, log2 37 = log2 a so that a = 37) ; (b) 3log3 8 = 8 ; (c) e (ln5) = 5
8. (a) e(ln ) = ; (b) 10log 5 = 5 ( if the base of log is not mentioned, it is assumed to be10) ; (c) 10log 87 = 87
9.(a) log5 x = 4, then x = 54 = 625 ; (b) log10 (0.1) = x or, x = log10(10-1) = -1 log10 10 = -1
10(a) log4 2 = x or, x = log4 (4)1/2 = (1/2) log4 4 = 1/2 ; (b) log4 x = 2, then x = 42 = 16.
Please post the remaining questions again.

