A vector a is parallel to the line of intersection of the plane determined by the vectors i, i+j and the plane determined by the vectors i-j, i+k. The obtuse angle between a and the vector b=i-2 j+2 k is:

Three Dimensional Geometry: JEE Main 2022 Mathematics question

JEE Main 2022 · 26 Jul, Evening shift · Q2596

JEE Main 202226 Jul, Evening shiftMathematicsHardThree Dimensional Geometry249× since 2002

A vector

\vec{a}

is parallel to the line of intersection of the plane determined by the vectors

\hat{i}, \hat{i}+\hat{j}

and the plane determined by the vectors

\hat{i}-\hat{j}, \hat{i}+\hat{k}

. The obtuse angle between

\vec{a}

and the vector

\vec{b}=\hat{i}-2 \hat{j}+2 \hat{k}

is :