Advanced Index Operations and Negative Powers
This page delves into more complex index operations, including working with negative and fractional powers, which are essential topics for National 5 Maths indices revision.
Negative powers indicate division. The general rule is: a⁻ᵐ = 1/aᵐ. For example, 3⁻² = 1/3².
Fractional powers represent roots. The general rule is: a^n/m = ᵐ√aⁿ. For instance, 15^2/3 = ³√15².
Highlight: When dealing with negative powers, remember the "flip" rule: move the term with the negative power from numerator to denominator orviceversa and make the power positive.
Examples of simplifying expressions with negative and fractional powers:
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Rewrite 3x⁻⁴ and 5y⁻³ using positive powers:
3x⁻⁴ = 1/3x4 and 5y⁻³ = 1/5y3
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Evaluate 9^3/4:
9^3/4 = 9(1/4)³ = ³√9³ = 3³ = 27
Vocabulary: A surd is a root squareroot,cuberoot,etc. of a number or expression that cannot be simplified to a whole or rational number.
The page also includes an example of simplifying a more complex expression: 3x²x2+2x3. This demonstrates how to apply the distributive property and combine like terms when working with indices.
These advanced concepts are crucial for tackling more challenging National 5 Maths indices questions and preparing for exams.