Let $\overline{\mathrm{a}}=\overline{\mathrm{i}}+2\overline{\mathrm{j}},$ $\overline{\mathrm{b}}=2\overline{\mathrm{j}}-\overline{\mathrm{k}}$  . If  $\overline{\mathrm{r}}\times \overline{\mathrm{a}}=\overline{\mathrm{b}}\times \overline{\mathrm{a}},$ $\overline{\mathrm{r}}\times \overline{\mathrm{b}}=\overline{\mathrm{a}}\times \overline{\mathrm{b}}$ ,then $\frac{\overline{\mathrm{r}}}{\left|\overline{\mathrm{r}}\right|}=$  

best study material, now at your finger tips!

• 

  live classes

• 

  progress tracking

• 

  24x7 mentored guidance

• 

  study plan analysis

download the app