The length of the perpendicular drawn from the point (2, 1, 4) to the plane containing the lines r =( i + j )+λ( i +2 j - k ) and r =( i + j )+μ(- i…

The length of the perpendicular drawn from the point ($\displaystyle 2$, $\displaystyle 1$, $\displaystyle 4$) to the plane containing the lines $$\begin{aligned} & \vec{r}=(\hat{i}+\hat{j})+\lambda(\hat{i}+2 \hat{j}-\hat{k}) \quad \text { and } \\ & \vec{r}=(\hat{i}+\hat{j})+\mu(-\hat{i}+\hat{j}-2 \hat{k}) \text { is: } \end{aligned} $$