Precalculus Logarithmic Expressions

Rewrite log₂8 = 3 in exponential form

• 2⁸ = 3

• 2³ = 8

• 3² = 8

• 8³ = 2

Write in exponential form.
log₂(¹/₈) = -3

• 2^-3 = ¹/₈
• 2^1/8 = -3
• -3² = ¹/₈
• -3^1/8 = 2

To evaluate a logarithm statement log₉81, you think "9 to what power is 81".

• True, and it's 2

• False

Evaluate the log by thinking " 3 to what power is 1/9" so

log₃(1/9) =

• 1/2

• 2

• -2

• 3

Evaluate by thinking 4 to what power is 16, so

log₄16

• 2

• 4

• 1/2

• -2

True or False: log₈64=2

• True
• False

Rewrite log₂8 = 3 in exponential form.

• 2⁸ = 3

• 2³ = 8

• 3² = 8

• 8³ = 2

Write 2³= 8 in logarithmic form.

• log₂ 8 = 3
• log₂ 3 = 8
• log₃ 8 = 2
• log₃ 2 = 8

Write log₃ 81 = 4 in exponential form.

• 81⁴=3
• 81³=4
• 4³=81
• 3⁴=81

Write log₆ 216 = 3 in exponential form.

• 3⁶=216
• 6³=216
• 216⁶=3
• 3²¹⁶=6