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Determine whether the vectors u and v are parallel, orthogonal, or neither.

u = <10, 6>, v = <9, 5>

1 Answer

7 votes

\mathbf u\cdot\mathbf v=\|\mathbf u\|\|\mathbf v\|\cos\theta

where
\theta is the angle between the vectors. You have


10*9+6*5=√(10^2+6^2)√(9^2+5^2)\cos\theta\iff \cos\theta=(30)/(√(901))\implies \theta\approx1.909^\circ

The vectors would be orthogonal if the dot product had been zero, but that's clearly not the case.

They would be parallel if the angle turned out to be
0^\circ or
180^\circ, but that's also not the case.

So the answer is neither.
User Dalle
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