If \[\mathbf{r}\,.\,\mathbf{i}=\mathbf{r}\,.\,\mathbf{j}=\mathbf{r}\,.\,\mathbf{k}\] and \[|\mathbf{r}|\,\,=3,\] then \[\mathbf{r}=\]

\[\pm \,3\,(\mathbf{i}+\mathbf{j}+\mathbf{k})\]

\[\pm \,\frac{1}{3}\,(\mathbf{i}+\mathbf{j}+\mathbf{k})\]

\[\pm \,\frac{1}{\sqrt{3}}\,(\mathbf{i}+\mathbf{j}+\mathbf{k})\]

\[\pm \,\sqrt{3}\,(\mathbf{i}+\mathbf{j}+\mathbf{k})\]

If \[\mathbf{r}\,.\,\mathbf{i}=\mathbf{r}\,.\,\mathbf{j}=\mathbf{r}\,.

1.	If \[\mathbf{r}\,.\,\mathbf{i}=\mathbf{r}\,.\,\mathbf{j}=\mathbf{r}\,.\,\mathbf{k}\] and \[\|\mathbf{r}\|\,\,=3,\] then \[\mathbf{r}=\]
A.	\[\pm \,3\,(\mathbf{i}+\mathbf{j}+\mathbf{k})\]
B.	\[\pm \,\frac{1}{3}\,(\mathbf{i}+\mathbf{j}+\mathbf{k})\]
C.	\[\pm \,\frac{1}{\sqrt{3}}\,(\mathbf{i}+\mathbf{j}+\mathbf{k})\]
D.	\[\pm \,\sqrt{3}\,(\mathbf{i}+\mathbf{j}+\mathbf{k})\]
Answer» E.

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If \[\mathbf{r}\,.\,\mathbf{i}=\mathbf{r}\,.\,\mathbf{j}=\mathbf{r}\,.\,\mathbf{k}\] and \[|\mathbf{r}|\,\,=3,\] then \[\mathbf{r}=\]

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