Logarithm question (1 Viewer)

mtsmahia

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Can someone help with this sum

Find the value of x

log(10) 2 + log(10) x = 2


answer is 50...can someone explain how it works?


thanks
 

tommykins

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log10 2x = 2 ----- log laws
2x = 10^2
x = 10^2/2 = 100/2 = 50.
 

suzlee

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mtsmahia said:
how did u get 2x= 10^2 (where did the log go?)


That's the law ..

You have to learn how to rearrange the log form into indice form
 

lyounamu

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mtsmahia said:
how did u get 2x= 10^2 (where did the log go?)
You can get rid of log by introducing the power of that.

For example, if you have

log10(100) = x
100 = 10^x
so x=2
 

mtsmahia

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suzlee said:
That's the law ..

You have to learn how to rearrange the log form into indice form
oh crap--im an idiot ...never thought about that--

thanks
 

studentcheese

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The general definition of a logarithm:

{(log base a)y} = x

can be rearranged into indice form

a^x = y

I think that's what it is.
 

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