alleryFor 2×2 matrix A = [[2,3],[1,4]], A⁻¹ =
A[[1/2,1/3],[1,1/4]]
BI
C(1/|A|) × [[4,-3],[-1,2]] = (1/5)[[4,-3],[-1,2]]
DSame as A
Answer & Solution
Correct answer: C. (1/|A|) × [[4,-3],[-1,2]] = (1/5)[[4,-3],[-1,2]]
|A| = 8 - 3 = 5. A⁻¹ = (1/|A|) × adj(A).
For 2×2 [[a,b],[c,d]]: adj = [[d,-b],[-c,a]].
**So A⁻¹ = (1/5)[[4,-3],[-1,2]].**
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