Math Is Fun Forum

djbip

Member

Registered: 2008-03-27

Posts: 13

easy logarithm that i can't solve! :P

log x + log 8 = 2       (the base is 10)

i need to solve without the use of a calculator

TheDude

Member

Registered: 2007-10-23

Posts: 361

Re: easy logarithm that i can't solve! :P

Use the rule log(a) + log(b) = log(ab).  Applying this rule to your example you'd get log(x) + log(8) = log(8x) = 2.  It should be fairly straightforward to solve from there.

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Wrap it in bacon

moxiuming

Member

Registered: 2008-04-20

Posts: 7

Re: easy logarithm that i can't solve! :P

we call logarithm function with base 10 common logarithm and it was denoted by lgx. TheDude had gave you the right answer.