Question

if $A=\left[\begin{array}{ccc}2& 2& 1\\ 1& 3& 1\\ 1& 2& 2\end{array}\right],$ then $A^3-7A^2+10A=$

• A. $5I+A$
• B. $5I-A$
• C. $5I$
• D. $6I$

Answer 1

Answer: (B)

Correct answer is (b) $5I-A$