Master all exponent laws and their applications. Math 10-C Alberta mathematics curriculum.
Lesson 2.6 of Number Systems & Operations in Math 10C — Alberta curriculum lessons.
Why a Complete Reference?. You have seen most of these laws before in earlier lessons. This tab collects all eight laws in one place so you can see how they fit together before applying them in combination.
An expression is considered fully simplified when: there are no brackets remaining, no negative exponents, and no zero exponents. Any negative exponents must be rewritten as positive exponents using the reciprocal rule.
Why Simplify Before Substituting?. When an expression contains variables and you need to evaluate it at specific values, always simplify the expression first using the exponent laws, then substitute.
This avoids messy arithmetic with large numbers. If you substitute first into something like (a^6b^9 ÷ a^5b^8)^(-2), you would need to compute (-3)^6 = 729 and 2^9 = 512 before doing anything else — far harder than simplifying first.
Worked Example — Evaluate (a^6b^9 ÷ a^5b^8)^(-2) when a = -3 and b = 2. Step 1 — Simplify the expression using exponent laws.
Apply the quotient rule inside the brackets:
(a^6b^9)/(a^5b^8) = a^(6-5) · b^(9-8) = a^1b^1 = ab
So the expression becomes:
(ab)^(-2)
Apply the negative exponent rule:
(1)/((ab)^2) = (1)/(a^2b^2)
Step 2 — Substitute a = -3 and b = 2.
(1)/((-3)^2 · 2^2) = (1)/(9 · 4) = (1)/(36)
Answer: (1)/(36)
The Rule for Multiplying. When multiplying two expressions with the same variable base, add the exponents on matching bases and multiply the coefficients together.
Example 1 — Simplify (3a^3b^(-2))(15a^2b^5). Step 1 — Multiply the coefficients.
3 × 15 = 45
Step 2 — Add the exponents on each base.
Base a: 3 + 2 = 5, so a^5
Base b: -2 + 5 = 3, so b^3
Answer: 45a^5b^3
Example 2 — Simplify (-2m^2n)(4mn^(-1)). Step 1 — Multiply the coefficients.
-2 × 4 = -8
Step 2 — Add the exponents on each base.
Base m: 2 + 1 = 3, so m^3
Base n: 1 + (-1) = 0, and n^0 = 1
Step 3 — Remove the zero exponent.
-8m^3 · 1 = -8m^3
Answer: -8m^3
Example 3 — Simplify m^4n^(-2) · m^2n^3. Step 1 — Add exponents on each base.
Base m: 4 + 2 = 6, so m^6
Base n: -2 + 3 = 1, so n^1 = n
Answer: m^6n
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