Quotient Rule

Reference > Algebra: Common Logarithms

Description

The Quotient Rule states that:

logbxy=logbxlogby\log_{b}{\frac{x}{y}}=\log_{b}{x}-\log_{b}{y}
Examples

Example 1

log29log23\log_{2}{9}-\log_{2}{3}
1
Use Quotient Rule: logbxy=logbxlogby\log_{b}{\frac{x}{y}}=\log_{b}{x}-\log_{b}{y}.
log293\log_{2}{\frac{9}{3}}

2
Simplify  93\frac{9}{3}  to  33.
log23\log_{2}{3}

Done

Decimal Form: 1.584963


 

Example 2

log34log32\log_{3}{4}-\log_{3}{2}
1
Use Quotient Rule: logbxy=logbxlogby\log_{b}{\frac{x}{y}}=\log_{b}{x}-\log_{b}{y}.
log342\log_{3}{\frac{4}{2}}

2
Simplify  42\frac{4}{2}  to  22.
log32\log_{3}{2}

Done

Decimal Form: 0.630930


 

Example 3

log2alog2b\log_{2}{a}-\log_{2}{b}
1
Use Quotient Rule: logbxy=logbxlogby\log_{b}{\frac{x}{y}}=\log_{b}{x}-\log_{b}{y}.
log2ab\log_{2}{\frac{a}{b}}

Done