Which expression represents a valid unit vector ?
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Answer: D. Both B and C are correct
Explanation
A valid unit vector must have a total calculated magnitude of exactly one. Squaring components of options B and C sums to one under square roots. Both mathematical representations satisfy the strict normalization condition for unit vectors. Vector magnitude is calculated using the square root of squared component sums. Normalizing a vector involves dividing each component by the vector magnitude. Unit vectors are dimensionless geometric tools used for directional specification.
Linear algebra computations frequently require normalized unit vectors for directional math. Physics simulations use unit vectors to calculate clean directional forces easily. Engineering design software relies on normalized vectors for spatial coordinate systems. Option A fails because squaring its components exceeds a magnitude of one. Option B is correct but incomplete since option C is also valid. Option C is correct but incomplete because option B is also valid.
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