Two square matrices $A , B$ satisfy
$$A ^ { 2 } + B = 3 E , \quad A ^ { 4 } + B ^ { 2 } = 7 E$$
Which of the following are correct? Choose all that apply from <Remarks>. (Here, $E$ is the identity matrix.) [4 points]
\textbf{Remarks}\\
ㄱ. $A B = B A$\\
ㄴ. $B ^ { - 1 } = A ^ { 2 }$\\
ㄷ. $A ^ { 6 } + B ^ { 3 } = 18 E$\\
(1) ㄱ\\
(2) ㄴ\\
(3) ㄱ, ㄴ\\
(4) ㄱ, ㄷ\\
(5) ㄱ, ㄴ, ㄷ