Home › JEE Advanced › Algebra › Which of the following is a diagonal matrix?
Which of the following is a diagonal matrix?
A$\begin{bmatrix}1&2\\0&3\end{bmatrix}$
B$\begin{bmatrix}0&0\\0&0\end{bmatrix}$
C$\begin{bmatrix}4&0&0\\0&-1&0\\0&0&2\end{bmatrix}$
D$\begin{bmatrix}1&1\\1&1\end{bmatrix}$
Answer & Solution
Correct answer: C. $\begin{bmatrix}4&0&0\\0&-1&0\\0&0&2\end{bmatrix}$
In a diagonal matrix, every non-diagonal entry must be zero. Option C satisfies this exactly. Although the zero matrix in option B also has all off-diagonal entries zero, the chapter separately defines zero/null matrix; the clearest standard example of a diagonal matrix here is option C.
Related questions
Simplifying an equation, a student reaches a statement that can never be true. The equatioAfter squaring both sides of a radical equation, a student finds a root that fails the oriSolving such an equation, a student clears every denominator at once by multiplying througAn equation contains at least one rational expression, with a variable in a denominator. TTo clear a complex number from a denominator, a student multiplies by the term found by flComplex numbers cannot sit on an ordinary number line, so they are plotted on a plane whosRather than drawing a number line, a student writes the solution set with brackets and parA statement joins two inequalities together in one line, such as 2 < x < 7. That statement