Math Fundamentals18 sections · 814 units
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Negative Exponents

Reciprocal of positive power

A negative exponent means "take the reciprocal." So xn=1/xnx^{-n} = 1 / x^n.

For example, 23=1/23=1/82^{-3} = 1 / 2^3 = 1 / 8. Instead of multiplying 2 by itself, you divide by 2 repeatedly. Or you compute the positive power and flip it.

This definition keeps the quotient rule working: x2/x5=x25=x3=1/x3x^2 / x^5 = x^{2-5} = x^{-3} = 1/x^3. The pattern holds without exceptions.