CUET Mathematics 2025 29 May Shift 2 PYQs

If $\begin{bmatrix} a-b & 0 & 0 \\ 0 & b-c & 0 \\ 0 & 0 & c-2 \end{bmatrix}$ is a scalar matrix such that $a + b + c = a$, then, which of the following are TRUE?

(A) $a = 0$

(B) $b = 0$

(C) $a = 1$

(D) $c = 1$

Choose the correct answer from the options given below:

For what value of $k$, the following system have a unique solution? (where $\mathbb{R}$ is set of real numbers)

$x + y + z = 1$

$2x + 3y + 4z = 3$

$x - y + kz = 5$

The system of equations

$x + ky = 0$

$3x + 5y = 0$

has infinitely many solutions, then k is equal to