The vector ` vec r` is inclined at equal acute angles of x-axis,y axis, and z-axis. If `| vec r|=6\ ` units, find ` vec rdot`

Explanation

Неге, `alpha=beta=gamma`

`Rightarrow cos alpha=cos beta=cos gamma `

`Rightarrow l=m=n=p(text { say })`

Now, we know that -

`l^{2}+m^{2}+n^{2}=1 `

`Rightarrow p^{2}+p^{2}+p^{2}=1 `

`Rightarrow 3 p^{2}=1 `

`Rightarrow p=pm frac{1}{sqrt{3}}`

...