Powers of Negative Numbers
Part of the Exponents & Polynomials section of Coddy's Algebra journey. Lesson 3 of 64.
A negative base follows the same factor counting, plus the sign rules you already know. (-2)^2 is (-2) * (-2), two negatives, so the result is positive 4. (-2)^3 multiplies one more negative in, flipping the sign: -8.
Each extra factor of a negative number flips the sign once, so the pattern is decided by the exponent alone: an even exponent gives a positive result, an odd exponent keeps the result negative. (-1)^100 is 1; (-1)^101 is -1.
The size of the answer ignores the sign entirely: (-2)^5 has the same size as 2^5, namely 32. Work out the size by counting factors, then let the parity of the exponent choose the sign.
Challenge
EasyUnpack (-2)^4 and multiply it down, watching the sign flip at every step.
Try it yourself
Simplify the expression
This lesson includes a short quiz. Start the lesson to answer it and track your progress.
All lessons in Exponents & Polynomials
1What a Power Is
Repeated MultiplicationSquares and CubesPowers of Negative NumbersWhere the Minus LivesRecap: First Powers4Power of a Power
A Power Raised AgainWhy Exponents MultiplyProduct Rule or Power Rule?The Rule in LettersRecap: Power of a Power2The Product Rule
Multiplying Same BasesWith CoefficientsMore Than Two FactorsThe Rule in LettersRecap: The Product Rule5Product and Quotient Powers
Every Factor Gets the PowerWith a Number InsideA Power of a QuotientAll Three Rules TogetherRecap: Products and Quotients8What a Polynomial Is
Terms with PowersThe DegreeLike Terms, Only StrongerRecap: Meet the Polynomials11Dividing by a Monomial
Splitting the FractionDividing by a Variable TermBigger SplitsCancel with CareRecap: Dividing3The Quotient Rule
Dividing Same BasesWhy Exponents SubtractWith CoefficientsThe Rule in LettersRecap: The Quotient Rule6Zero and Negative Exponents
The Zero ExponentZero at WorkNegative Means ReciprocalWriting Without NegativesPowers of TenRecap: Zero and Negative