Question
Proof Prove that$$\mathbf{u}=(\cos \theta) \mathbf{i}-(\sin \theta) \mathbf{j} \quad$ and $\quad \mathbf{v}=(\sin \theta) \mathbf{i}+(\cos \theta) \mathbf{j}$$are unit vectors for any angle $\theta$
Step 1
The magnitude of a vector is given by the square root of the sum of the squares of its components. So, for $\mathbf{u}$, we have: $$|\mathbf{u}| = \sqrt{(\cos \theta)^2 + (-\sin \theta)^2}$$ Show more…
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