5A Logs Intro

Rewrite into exponential form:  $\log_AB=C$  

•  $A^C=B$  

•  $C^B=A$  

•  $B^C=A$  

•  $A^B=C$  

•  $C^A=B$  

Rewrite into exponential form:  $\log x=y$  

•  $1^x=y$  

•  $1^y=x$  

•  $10^x=y$  

•  $10^y=x$  

•  $y^x=10$  

Rewrite into log form:  $3^x=y$  

•  $\log_3x=y$  

•  $\log_3y=x$  

•  $\log_xy=3$  

•  $\log_yx=3$  

•  $\log_x3=y$  

 $e^A=B$  Rewrite into log form:

•  $\ln A=B$  

•  $\ln B=A$  

•  $\log_Be=A$  

•  $\log_BA=e$  

•  $\log_Be=A$  

Evaluate $\log_381$  You need to be able to do this without a calculator!

• 3

• 9

• 27

• 4

Evaluate $\log_{25}5$  You need to be able to do this without a calculator!

• 5

• 1/5

• -2

• 1/2

• -1/2

Evaluate $\log_6\left(\frac{1}{36}\right)$  You need to be able to do this without a calculator!

• 2

• -2

• 6

• -6

• -1/2

Evaluate $\ln1$  You need to be able to do this without a calculator!

• 1

• e

• 0

• 10

Evaluate $\log_{25}125$  You need to be able to do this without a calculator!

• 2

• 3

• 3/2

• 2/3

• -2/3

Evaluate $\log_{\sqrt{3}}27$  You need to be able to do this without a calculator!

• 3

• 3/2

• 6

• 9