Mathematics - 3D-Coordinate Geometry Question with Solution | TestHub

Direction ratios of line OP are $1,\sqrt{2},1$. Hence direction cosines of line OP are $\frac{1}{\sqrt{1+2+1}},\frac{\sqrt{2}}{\sqrt{1+2+1}},\frac{1}{\sqrt{1+2+1}}=\frac{1}{2},\frac{1}{\sqrt{2}},\frac{1}{2}$ Hence angles made with given planes are $60^{\circ },45^{\circ },60^{\circ }$