Definition of Logarithm

Logarithms are the inverse of (a)   .

• Trees
• Quadratic Equations
• Squaring
• Exponential Equations

What is the name of the b in this equation?

• log

• base

• exponent

• argument

What is the name of the x in this equation (particularly if rewritten as an exponential equation)?

• log

• base

• exponent

• argument

Rewrite log₂8 = 3 in exponential form

• 2⁸ = 3

• 2³ = 8

• 3² = 8

• 8³ = 2

Change to Exponential Form: log₆36 = x ​ (a)   ​

Change y = a^x into log form.

• x = log_ay

• y = log_ax

• x = log_ya

• y = log a

Rewrite 3⁴ = 81 in logarithmic form.

• log₃4 = 81
• log₈₁3 = 4
• log₃81 = 4
• log₄81 = 3

Write in logarithmic form.
2^-4 = ¹/₁₆

• log₂(¹/₁₆) = -4
• log_-4(¹/₁₆) = 2
• log _-4 2 = ¹/₁₆
• log₂(-4) = ¹/₁₆