7) Find A such that A = 2 and adj A = 2 2 0 2 5 1 0 1 1 Share with your friends Share 1 Sanjay Kumar Manjhi answered this Dear Student,Given, adj(A)=220251011 and det(A)=2Let, A=abcdefghiWe know that,A×adj(A)=det(A)×I⇒abcdefghi×220251011=2×100010001⇒2a+2b2a+5b+cb+c2d+2e2d+5e+fe+f2g+2h2g+5h+ih+i=200020002Now,2a+2b=2⇒a=1-b........(i)and, b+c=0⇒c=-b.........(ii)and, 2a+5b+c=0put the value of a and c from (i) and (ii) in (iii), we get;⇒2(1-b)+5b-b=0⇒2+2b=0⇒b=-1From (i), we get;a=1-(-1)⇒a=2From (ii), we get;c=1...............................2d+2e=0⇒d=-e..............(iv)and, e+f=0⇒f=-e...............(v)and, 2d+5e+f=2..........(vi)put the value of d and f from (iv) and (v) in (vi), we get;⇒-2e+5e-e=2⇒2e=2⇒e=1From (iv), we get;d=-1From (v), we get;f=-1.........................................2g+2h=0⇒g=-h.............(vii)and, h+i=2⇒i=2-h............(viii)and, 2g+5h+i=0..............(ix)put the value of g and i from (vii) and (viii) in (ix), we get;⇒-2h+5h+2-h=0⇒2h=-2⇒h=-1From (vii), we get;g=1From (viii), we get;i=2-(-1)⇒i=3So,A=2-11-11-11-13Regards. 0 View Full Answer