NDA 2015
- Exam
- NDA
- Year
- 2015
- Subject
- Mathematics
- Chapter
- Determinants
NDA 2015 · Mathematics · Determinants
If a, b, c are real numbers, then the value of the determinant |...
If are real numbers, then the value of the determinant
\left|$$\right|
Options
- A0
- B
- C
- D
Correct answer
A. 0
Step-by-step solution
\left|\right|$
apply \mathrm{C}_2 \rightarrow \mathrm{C}_2+\mathrm{C}_3\left|\begin{array}{lll}
1-a & a & b+c \\
1-b & b & c+a \\
1-c & c & a+b
\end{array}\right|$
apply $\mathrm{C}_1$ \rightarrow $\mathrm{C}_1+\mathrm{C}_2\left|\begin{array}{lll}
1 & \mathrm{a} & \mathrm{~b}+\mathrm{c} \\
1 & \mathrm{~b} & \mathrm{c}+\mathrm{a} \\
1 & \mathrm{c} & \mathrm{a}+\mathrm{b}
\end{array}$\right|$
apply \mathrm{C}_3 \rightarrow \mathrm{C}_2+\mathrm{C}_3(\mathrm{a}$+$\mathrm{b}+\mathrm{c})\left|\begin{array}{lll}
1 &\mathrm{a}& 1 \\
1 &\mathrm{~b}& 1 \\
1 &\mathrm{c}& 1
\end{array}$\right|=0