Practicing Success
Practicing Success
CUET Preparation Today
If A is a square matrix of order $3×3$ such that $A^2=A$ and I is the unit matrix of order $3× 3$, then the value of $(I-A)^3+A^2+I$ is : |
0 I 2I 4I |
2I |
The correct answer is Option (3) → $2I$ $(I-A)^3+A^2+I$ $=I^3-A^3-3I^2A+3IA^2+A^2+I$ $=I-A-3A+3A+A+I$ $=2I$ |
