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Algebra 2 Section 6-1. Roots of Real Numbers. In General:. RADICAL SIGN. For EVEN roots, the radicand must be 0 and there are two roots, the principal (or positive) root and its additive inverse (opposite). For ODD roots, there is exactly one root for any value of the radicand. INDEX.
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Algebra 2Section 6-1 Roots of Real Numbers
In General: RADICAL SIGN For EVEN roots, the radicand must be 0 and there are two roots, the principal (or positive) root and its additive inverse (opposite). For ODD roots, there is exactly one root for any value of the radicand. INDEX RADICAND
A square root of a number b is a solution of the equation . Example 1: Every positive number b has two square roots, denoted by Example 2: The square root of a real number is never negative because the equation has no real-number solution if b < 0.
WHY? 5 is the principal square rootof 25! We NEVER use the negative one unless we are solving an equation!
Cubes? Example 3: A cube root of a number b is a solution of the equation . Example 4: Example 5: Every number b has exactlyone cube root, denoted by Example 6:
When? Example 7: So, when is it OK to use the other root (the negative one) when doing EVEN roots?? ONLY when solving EQUATIONS!
Example 9: Notice the extra step!!