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Guyz in Mathematics this a way in which we can find the exponent of a number by Log

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How can we do that if anyone can please tell me i will be so grateful :D please ;)
if its lets say 2^x = 512
you should do it like this "log 512 / log 2" then u can check
if its 2 marks you gotta change the bases and show them how you got it
 
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if its lets say 2^x = 512
you should do it like this "log 512 / log 2" then u can check
if its 2 marks you gotta change the bases and show them how you got it
Thankies!! :D

this kind of answer is usually for 1 mark
AOA,
Here:

ln is natural log, it stands for log base 'e' and you should know that:
ln e = 1
ln 1 = 0
if equation such as this is given:
ln x = 5
then
x = e^5
Similarly if an equation such as this is given:
e^x = 5
then taking ln on both sides
x lne = ln5 (lne = 1)
x = ln5

lg is general log, it stands for log base '10' and you should know that:
lg 10 = 1
lg 1 = 0
if equation such as this is given:
lg x = 8
then
x = 10^8
Similarly if an equation such as this is given:
10^x = 8
then taking lg on both sides
x lg10 = lg8 (lg10 = 1)
x = lg 8

Another type of question can be this:
3^x = 5
Now, its your choice either you can take ln of both sides or lg of both sides
Im taking ln of both sides
ln(3^x) = ln5
x ln3 = ln5
x = ln5/ln3
 
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AOA,
Here:

ln is natural log, it stands for log base 'e' and you should know that:
ln e = 1
ln 1 = 0
if equation such as this is given:
ln x = 5
then
x = e^5
Similarly if an equation such as this is given:
e^x = 5
then taking ln on both sides
x lne = ln5 (lne = 1)
x = ln5

lg is general log, it stands for log base '10' and you should know that:
lg 10 = 1
lg 1 = 0
if equation such as this is given:
lg x = 8
then
x = 10^8
Similarly if an equation such as this is given:
10^x = 8
then taking lg on both sides
x lg10 = lg8 (lg10 = 1)
x = lg 8

Another type of question can be this:
3^x = 5
Now, its your choice either you can take ln of both sides or lg of both sides
Im taking ln of both sides
ln(3^x) = ln5
x ln3 = ln5
x = ln5/ln3
That is what A2 or AS level CUZ i really DID NOT UNDERSTAND A SINGLE WORD!~!
 
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LOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOL!!!!!!! IAM JUST GOING WITH MY TEACHER'S WAY LOL Iam an IGCSE student not O'level WOWOWOWOWOW!!
 
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Ok go on!
But you will come across this,
and its very easy once you learn this once
 
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