If $\overrightarrow A = 2\hat i + 4\hat j - 5\hat k$ the direction of cosines of the vector $\overrightarrow A $ are

  • A
    $\frac{2}{{\sqrt {45} }},\frac{4}{{\sqrt {45} }}\,{\rm{and}}\,\frac{{ - \,{\rm{5}}}}{{\sqrt {{\rm{45}}} }}$
  • B
    $\frac{1}{{\sqrt {45} }},\frac{2}{{\sqrt {45} }}\,{\rm{and}}\,\frac{{\rm{3}}}{{\sqrt {{\rm{45}}} }}$
  • C
    $\frac{4}{{\sqrt {45} }},\,0\,{\rm{and}}\,\frac{{\rm{4}}}{{\sqrt {45} }}$
  • D
    $\frac{3}{{\sqrt {45} }},\frac{2}{{\sqrt {45} }}\,{\rm{and}}\,\frac{{\rm{5}}}{{\sqrt {{\rm{45}}} }}$

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