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STD 12 - 3 and 4 . determinant and metrices — JEE STD 11 Science — Question

Gujarat BoardEnglish MediumSTD 11 ScienceJEESTD 12 - 3 and 4 . determinant and metrices4 Marks
MCQ
If $A = \left( {\begin{array}{*{20}{c}}
2&{ - 1}\\
{ - 7}&4
\end{array}} \right)$ and $B = \left( {\begin{array}{*{20}{c}}
4&1\\
7&2
\end{array}} \right)$ then which of the following is correct
  • A
    $AA^T = I$
  • ✓
    $(AB)^T = I$
  • C
    $BB^T = I$
  • D
    $AB \neq  BA$
✓

Answer

Correct option: B.
$(AB)^T = I$
b

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