Question

If $A=\begin{vmatrix}x&1\\\1&x\end{vmatrix}$ and $B=\begin{vmatrix}x &1&1\\\1& x&1 \\\1&1&x \end{vmatrix}$,then $\frac{dB}{dx}$ is

• A. 3A
• B. –3B
• C. 3B + 1
• D. 1 – 3A

Answer 1

Answer: (A)

3A

Answer 2

The correct answer is Option (A) : 3A