0 votes 0 votes If 2 and -4 are the eigenvalues of a non-singular matrix A and |A| = -8, then the eigenvalues of adj(A) are x and -y. What is the value of x+y? Linear Algebra linear-algebra engineering-mathematics made-easy-test-series eigen-value + – atulcse asked Jan 13, 2022 atulcse 397 views answer comment Share Follow See all 4 Comments See all 4 4 Comments reply atulcse commented Jan 13, 2022 reply Follow Share my answer: 6 how i solved: eigenvalues of adj(A) = |A| / eigenvalues of A = -8/2 and -8/-4 = -4 and 2. hence, x = 2, y = 4. so, x + y = 6. however, answer key: -6 0 votes 0 votes ramakrushna commented Jan 13, 2022 reply Follow Share X= (-8)/2 = – 4 Y= (-8)/-4 = 2 But Adj of A is given X and -Y so values will be X= -4 and -Y = -2 So total would be -4 -2 = -6 Answer key is correct. 1 votes 1 votes Isha_99 commented Jan 13, 2022 reply Follow Share You have solved it correctly @atulcse , test series often have this type of mistakes so don’t bother about this too much. 1 votes 1 votes aaa 1 commented Jan 17, 2022 reply Follow Share @atulcse A=[2 0 0 −4] ... Adj (A)= [−4 0 0 2 ] ... Here x=−4 and −y=2 ⇒y = −2 ⇒x+y = (−4) − 2 = −6 … 1. https://gateoverflow.in/290887/Made-easy 1 votes 1 votes Please log in or register to add a comment.