Question

if a is a singular then lambda(1a)^-1=​

Answer 1

Answer:

A−Iλ is a singular matrix

⇒A−Iλ=0

⇒[1232]−λ[1001]=0

⇒[1232]−[λ00λ]=0

⇒∣∣∣∣∣∣1−λ232−λ∣∣∣∣∣∣=0

⇒(1−λ)(2−λ)−6=0

⇒2−λ−2λ+λ2−6=0

⇒λ2−3λ−4=0

⇒λ2−4λ+λ−4=0

⇒λ(λ−4)+1(λ−4)=0

⇒(λ−4)(λ+1)=0

Correct option is

A

λ=4

B

λ2−3λ−4=0

C

λ=−1

i hope my answer is correct any doubt you can ask me thank you