Logarithm of a power

log⁡axk=klog⁡ax\log_a x^k=k\log_a x

Result unit: — (liczba)

What it describes

The logarithm of a power is the exponent multiplied by the logarithm of the power's base.

Symbols

aa
base
xx
positive number
kk
exponent

Where it comes from

The exponent “comes out in front of” the logarithm as a factor — exponentiation turns into multiplication.

When to use it

Logarithms of powers and roots; solving equations.

Example

Evaluate log⁡282\log_2 8^2.
Substitution2⋅log⁡282\cdot\log_2 8.
Result2⋅3=62\cdot3=6.

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