amp;amp;A=[21amp;−1amp;0]amp;A2=[32amp;−2amp;−1],A3=[43amp;−3amp;−2],A4=[54amp;−4amp;−3]amp; and so on amp;amp;A6=[76amp;−6amp;−5]amp;Am=[m+1 mamp;−mamp;−m+1],amp;Am2=[m2+1 m2amp;−m2amp;−(m2−1)]amp;Am2+Am=3I−A−6amp;[m2+1 m2amp;−m2amp;−(m2−1)]+[m+1 mamp;−mamp;−m+1]
amp;=3[10amp;0amp;1]−[−5−6amp;6amp;7]amp;=[86amp;−6amp;−4]amp;=m2+1+m+1=8amp;=m2+m−6=0⇒ m=−3,2amp;n( s)=2