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Laws of indices - EduqasDividing indices

Using indices, we can show a number times itself many times or as another way of writing a square or cube root. Indices make complex calculations that involve powers easier.

Part of MathsNumber

Dividing indices

Example

\(b^5 \div b^3\).

\(b^5 \div b^3\) can be written as \(\frac{b^5}{b^3}\) and writing out the and in full gives \(\frac{b \times b \times b \times b \times b}{b \times b \times b}\). There are common factors of \(b\) in the numerator and denominator and these can be cancelled out, giving \(\frac{\cancel{b} \times \cancel{b} \times \cancel{b} \times b \times b}{\cancel{b} \times \cancel{b} \times \cancel{b}}\) which leaves \(b \times b = b^2\).

This means \(b^5 \div b^3\) can be simplified to \(b^2\).