MathematicsMedium202×since 2002Q5819Let a→\overrightarrow aa be a vector which is perpendicular to the vector 3i^+12j^+2k^3\widehat i + {1 \over 2}\widehat j + 2\widehat k3i+21j+2k. If a→×(2i^+k^)=2i^−13j^−4k^\overrightarrow a \times \left( {2\widehat i + \widehat k} \right) = 2\widehat i - 13\widehat j - 4\widehat ka×(2i+k)=2i−13j−4k, then the projection of the vector a→\overrightarrow aa on the vector 2i^+2j^+k^2\widehat i + 2\widehat j + \widehat k2i+2j+k is :A13{1 \over 3}31B1C53{5 \over 3}35D73{7 \over 3}37Check answerSkip