diagonal matrix - prove

if D = diag(a₁ , a₂ , a₃ , ...... a_n), where a_i â‰ 0 for all i = 1,2....,n, then show that

D^-1 = diag(a₁^-1 , a₂^-1 , a₃^-1 , .......... a_n^-1).

1 Answers

one more
2) Let matrix âˆ‚ =
[cosA sinA]
[-sinA cosA],

where A = pi/5

Then B = A⁴ - A³ + A² - A is

(A)Singular (B)non-singular
(C)symmetric (D)|B| = 1

note : Its a multi-choice multi correct question

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