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MATHEMATICS · Single correct · CBSE · Mathematics · Three-Dimensional Geometry · Three-Dimensional Geometry
Problem The angle between the lines A B AB A B C D CD C D A = ( 0 , 0 , 0 ) A=(0,0,0) A = ( 0 , 0 , 0 ) B = ( 1 , 1 , 1 ) B=(1,1,1) B = ( 1 , 1 , 1 ) C = ( − 1 , − 1 , − 1 ) C=(-1,-1,-1) C = ( − 1 , − 1 , − 1 ) D = ( 0 , 1 , 0 ) D=(0,1,0) D = ( 0 , 1 , 0 ) cos θ = 1 3 \cos\theta=\frac{1}{\sqrt{3}} cos θ = 3 1 cos θ = 4 3 2 \cos\theta=\frac{4}{3\sqrt{2}} cos θ = 3 2 4 cos θ = 1 5 \cos\theta=\frac{1}{\sqrt{5}} cos θ = 5 1 cos θ = 1 2 2 \cos\theta=\frac{1}{2\sqrt{2}} cos θ = 2 2 1 Browse the problem library