Introduction to Logarithms (Conversions)

What does the abbreviation "log" stand for?

• Exponential

• Logarithm

• Logitech

What is the purpose of a logarithm?

• to make your friend smile

• to undo a square root

• to find a missing exponent

A logarithm is an inverse of...

• an exponent

• a square root

• a quadratic

 $\log_{16}256\ =\ 2$  

Rewrite in exponential form.

•  $16^2=256$  
  

•  $2^{16}=256$  
  

•  $\frac{256}{16}=2$  

 $The\ \frac{1}{8}\ in\ this\ equation:\log_2\frac{1}{8}=-3\ \ is\ the\ what...\$ 

• base

• exponent

• argument

 $\log_981\ =\ 2$  

Rewrite in exponential form.

•  $9^2=81$  
  

•  $2^9=81$  
  

•  $\left(9\right)\left(2x\right)\ =\ 81$  

 $3^5=243$  Rewrite in logarithmic form.

•  $\ln_{243\ }=\ 3$  

•  $\log_5243=3$  

•  $\log_3243=5$  

 $6^3\ =\ 216$  

Rewrite in logarithmic form.

•  $\log_6216=3$  

•  $\frac{196}{14}=\ 2$  

•  $\log_3216\ =6$  

 $x^y=\ 130$  Convert to logarithmic form.

•  $\log_{130}x=y$  

•  $\log_yx=130$  

•  $\log_x130=y$  

 $\log_525=x$  Solve for "x".

• x = 5

• x = 2

• x = 25