Find the Equation for the Plane Tangent to the Parametrized

Essay

Find the equation for the plane tangent to the parametrized surface S at the point P.
- $$\mathrm { S } \text { is the cone } \mathbf { r } ( \mathrm { r } , \theta ) = \mathrm { r } \cos \theta \mathbf { i } + \mathrm { r } \sin \theta \mathbf { j } + 4 \mathrm { rk } ; \mathrm { P } = ( - 5 \sqrt { 2 } , 5 \sqrt { 2 } , 40 ) \text {. }$$