MathematicsMedium244×since 2002Q4482Let A = \left[ {\matrix{ 1 & 2 \cr { - 1} & 4 \cr } } \right]. If A^−-−1 = α\alphaαI + β\betaβA, α\alphaα, β\betaβ ∈\in∈ R, I is a 2 ×\times× 2 identity matrix then 4(α\alphaα −-− β\betaβ) is equal to :A5B83{8 \over 3}38C2D4Check answerSkip