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We have (A⁻¹ - I)(A⁻¹ + I) = O
A⁻² - I = O
A⁻² = I
Multiplying both sides with A, we get
A⁻¹ = A
Multiplying both sides with A⁻¹, we get
I = A²
A² = I
Substituting this in αA + βA⁻¹ = 4I, we get
αA + βA = 4I
(α + β)A = 4I
Since A is non-singular, we can pre-multiply both sides by A⁻¹
(α + β)I = 4A⁻¹
(α + β)I = 4A (since A⁻¹ = A)
(α + β)A = 4I
From A² = I, we have A⁻¹ = A
Thus, αA + βA⁻¹ = αA + βA = (α + β)A = 4I
From (A⁻¹ - I)(A⁻¹ + I) = O
A⁻² - I = O
A⁻² = I
Multiplying by A² on both sides,
A⁻²A² = IA²
I = A²
So A² = I and A⁻¹ = A
Then αA + βA⁻¹ = 4I becomes αA + βA = 4I which means (α+β)A = 4I
Since A is non-singular, we can write A⁻¹ on the left side to get:
(α+β)AA⁻¹ = 4IA⁻¹
(α+β)I = 4A⁻¹
Since A⁻¹ = A, we get (α+β)I = 4A
(α+β)A = 4I
Since A²=I, A⁻¹=A, therefore A=A⁻¹
Given αA+βA⁻¹=4I
αA+βA=4I
(α+β)A=4I
(α+β)I=4A⁻¹=4A
Let's use A² = I
(A-I)(A+I) = 0
A²-I = 0
A² = I
This implies A⁻¹ = A
Substituting in αA + βA⁻¹ = 4I gives
αA + βA = 4I
(α+β)A = 4I
Pre-multiplying by A⁻¹
α+β = 4A⁻¹
Since A⁻¹ = A, α+β = 4A which is not helpful
(α+β)A = 4I
(α+β) = 4A⁻¹ = 4A
From (A⁻¹-I)(A⁻¹+I)=O, we have A⁻² - I = 0 which implies A²=I, so A⁻¹ = A
Substituting into αA + βA⁻¹ = 4I gives (α+β)A = 4I
Pre-multiply by A⁻¹ which is equal to A: (α+β)AA⁻¹ = 4A⁻¹
α+β = 4A⁻¹ = 4A
This is not helpful
Let's go back to (A⁻¹ - I)(A⁻¹ + I) = 0
A⁻² - I = 0
A⁻² = I
A² = I
A⁻¹ = A
αA + βA⁻¹ = 4I
(α+β)A = 4I
Pre-multiply by A⁻¹ = A
(α+β)A² = 4A
(α+β)I = 4A
(α+β) = 4A
This doesn't help. There must be a mistake in the problem statement or my calculations.