Which pair of vectors is collinear?

2\hat{i} - 3\hat{j} + \hat{k}

and

-4\hat{i} + 6\hat{j} - 2\hat{k}

Correct answerYour answer

\hat{i} + \hat{j}

and

\hat{j} + \hat{k}

Correct answerYour answer

2\hat{i} + \hat{j}

and

\hat{i} + 2\hat{j}

Correct answerYour answer

\hat{i} - \hat{j} + \hat{k}

and

\hat{i} + \hat{j} - \hat{k}

Correct answerYour answer

Show the answer and explanation

CorrectNot quiteAnswer A

Correct answer: A

Collinear vectors are scalar multiples of each other: their components are in one ratio.
$-4\hat{i} + 6\hat{j} - 2\hat{k} = -2(2\hat{i} - 3\hat{j} + \hat{k})$ ; no other pair has one ratio.

Worth noting

$2\hat{i} + \hat{j}$ and $\hat{i} + 2\hat{j}$ use the same numbers, but in a different order, so the ratios are 2 and $\frac{1}{2}$ .

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