Monday, 6 February 2017

Topic 6: Logarithms with Exercises

What is Logarithms?
A logarithms is a simple given number that be produce which can be raised by representing the the quantity of power to fixed the number. (base)

Basic simple of using the logarithms:



Example 1:
How many 2's do we multiply to get 8?

Answer:
2 x 2 x 2 = 8, so we had to multiply 3 of the 2's to get 8
So, the logarithm is 3

Example 2:
What is Log 5 625?
How many 5's is needed to be multiplied together to get 625?
5 x 5 x 5 x 5 = 625, so we need to be 4 of the 5's

Answer:
Log 5 625 = 4

Example 3:
What is Log 4 64?How many 2's need to be multiplied together to get 64?
 2 x 2 x 2 x 2 x 2 x 2 = 64, so we need 6 of the 2's

Answer:
Log 4 64 = 6


An Exponents




It's how many times to use the number in multiplications.
Example:82 = 8 x 8 = 64

(2 is used 2 times in a multiplication to get 64)




So if a logarithm answer a question like this:
 2? = 8

so this way,



The logarithm tell us what the exponent is!

In that example the base is 2 and the exponent is 3:

2^3=8 becomes log_2(8)=3
what exponents that we need?
the general case:
a^x=y becomes log_a(y)=x


Example 1:
What is  Log 10 100 ?
102 = 100
So an exponent of 2 is needed to make 10 into 100, and:

Log 10 100 = 2

Example 2:
What is  Log 3 81 ?
So an exponent of 4 is needed to make 3 into 81 and:

Log 3 81 = 4

Example 3:
What is Log 3 27?
So an exponent of 3 is needed to make 3 into 27 and:

Log 3 27 = 3




HERE IS SOME VIDEO FOR YOUR UNDERSTANDING. 





-EXERCISE-
!GOOD LUCK!


Question 1:
 What is log 256?

Question 2:
 What is log 729?

Question 3: 

 Given that 32 = 9 in exponent from, how would you write this in logarithm form?



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