Find the angle between the lines whose direction cosines are given by the equations `3l+m+5n=0,6m m-2n l+5l=0`

Explanation

Eliminating m from the given 2 equations, we get

`
Rightarrow 2 n^{2}+3 l n+l^{2}=0 `
`
Rightarrow (n+l)(2 n+l)=0 `
`
Rightarrow { either } n=-l { or } l=-2 n `

Now if ` l=-n, { then } m=-2 n `

and if ` l=-2 n, { then } m=n . `


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