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An even root is being taken. What must be true of the radicand for the root to be real?
AIt must be negative
BIt must be positive
CIt must be a fraction
DIt must be a decimal
Answer & Solution
Correct answer: B. It must be positive
1. The radicand is the number sitting under the root sign.
2. For an even root, the radicand must be positive, otherwise the roots are not real.
3. Squaring any real number gives a positive answer, so nothing squares to give a negative number.
4. An odd root is the other case, where the radicand may be positive or negative.
_Source: Siyavula Mathematics Grade 11 (Everything Maths, CC BY 4.0), Chapter 1: Exponents and surds_
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