Laws of Logarithms

  Log (AB) = Log A + Log B

  Log (A/B) = Log A – Log B

  Log (A^x) = X Log A

                                          Example Question

Simple the following without using tables

1.    Log 16 ÷Log 4

2.    Log 24 – Log6÷ Log 16

                          Solution

1)   Log 16÷Log 4

 

= Log 2x2x2x2÷Log 2x2

 

= Log 2⁴÷Log 2²

= 4Log 2÷2Log2

= 2

2)   Log 24 – Log6÷ Log 16

 

                Solution

Log 24 – Log 6÷ Log 16

 

Log (8x3) – Log (2x3) ÷ Log (2x2x2x2)

 

Log (2³x3) - Log (2x3) ÷ Log2⁴

 

Log 2³+Log3 – (Log2+Log3) ÷Log2⁴

 

3Log2+Log3-Log2- Log3÷ 4Log2

 

2Log2÷ 4Log2

 

= 1/2