College Algebra / Unit 8 Alg 433 short lesson, about 20 seconds
Evaluating Logarithms Mentally
Captions available
The idea
A logarithm evaluates mentally by asking the exponent question aloud: what power of this base makes this input?
In practice
log₂(32) = 5, since 2⁵ = 32; log₉(3) = 1/2, since 9^(1/2) = 3; log₇(1) = 0, since anything to the 0 is 1.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
Builds on
- Nothing. This is a starting point.
Unlocks
- Nothing yet depends on this.
Something wrong in this lesson? Flag it · Sources for College Algebra