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Fri 13 Jul, 2007 08:23 pm
I know about log and all this stuff about logax being equivalent to a^y=x. what i dont understand is how it relates to the world of maths...what exactly is log... and how did it come about... what use is it. tell me answer me and excuse my dumbness im not as old aND WISE as you people
Think about a number to a common base. Say base 10 the any real number can be expressed as a logarithm to that base say a is any real number and b is it's base ten (10) logarithm.
So a=10^b or b=log10(a)
Now consider the rules of exponents
!0^x*10^y=10^(x+y)
!0^x/10^y=10^(x-y)
(10^x)^y=10^(xy)
& so on
Using the rules of exponents and logarithms to a common base you can treat multilication and division like addition and subtraction and exponenation like multiplication. In other words its a sidestep of operations that allows one to simplify the arithmetic.
Example I have two really big numbers a1 and a2. I want to multiply them. I can take the base ten logarithm of a1 such that a1=10^b1 and a2=10^b2. The the logarithm of the mutiple (a1*a2) is the sum of b1 and b2 or
a1*a2=10^b1*10^b2=10^(b1+b2)
division is treated as subtraction.
Look at the rules of exponiation and you'll get an inkling of the utility of logaritms.
Rap
now i realise why i chose art instead of math ROFL. someone learn meh sum math skilz por favor?
wow raprap ur smart! thanks