MCQ
The vectors $2\,i + 3\,j - 4\,k$ and $a\,i + b\,j + c\,k$ are perpendicular, when
- A$a = 2,\,\,b = 3,\,\,c = - 4$
- ✓$a = 4,\,\,b = 4,\,\,c = 5$
- C$a = 4,\,\,b = 4,\,\,c = - \,5$
- DNone of these
✓
Answer
Correct option: B.
$a = 4,\,\,b = 4,\,\,c = 5$
b
(b) To be perpendicular, $2a + 3b - 4c = 0$ and option $(b)$ satisfies this equation.
(b) To be perpendicular, $2a + 3b - 4c = 0$ and option $(b)$ satisfies this equation.
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