MCQ
જો $a = i + j +k, a.b = 1 $ અને $a \times b = j - k,$ તો $b = …….$
- A$i$
- B$i - j + k$
- C$2j - k$
- D$2i$
હવે $j - k = a \times b = \left| {\begin{array}{*{20}{c}} i&j&k \\ 1&1&1 \\ {{b_1}}&{{b_2}}&{{b_3}} \end{array}} \right|$
$\,{b_3} - {b_2} = 0,{b_1} - {b_3} = 1,{b_2} - {b_1} = - 1$
$ \Rightarrow \,\,{b_3} = {b_2},{b_1} = {b_2} + 1$
હવે $a.b = 1$
$ \Rightarrow {b_1} + {b_2} + {b_3} = 1$
$ \Rightarrow \,\,3{b_2} + 1 = 1$
$ \Rightarrow {b_2} = 0$
$ \Rightarrow \,{b_1} = 1,{b_3} = 0$
આથી $b = i$
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.