A vector is known to have magnitude

MATHEMATICS · Subjective · AP · AP Precalculus · Functions with Parameters, Vectors, and Matrices · Functions with Parameters, Vectors, and Matrices

Problem

A vector

\mathbf{r}=k\,\hat{i}+4\,\hat{j}-3\,\hat{k}

is known to have magnitude

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. (i) Find the value(s) of

k

. (ii) For each value of

k

obtained, write the corresponding unit vector in the direction of

\mathbf{r}

. (iii) Verify that each unit vector you have written indeed has magnitude

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