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Find the inverse of the matrix if it exists. [-7 4] [8 -5]

User Waddah
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Final answer:

To find the inverse of a 2x2 matrix, use the formula A⁻¹ = 1/det(A) * adj(A). Calculate the determinant and adjugate matrix, then multiply by the reciprocal of the determinant.

Step-by-step explanation:

To find the inverse of a 2x2 matrix, we can use the formula:

A⁻¹ = 1/det(A) * adj(A)

Where det(A) is the determinant of matrix A and adj(A) is the adjugate matrix of A. For the given matrix [-7 4] [8 -5], we can calculate these values as follows:

det(A) = (-7 * -5) - (4 * 8) = 35 - 32 = 3

adj(A) = [-5 -4] [8 -7]

Therefore, the inverse of the matrix is:

A⁻¹ = 1/3 * [-5 -4] [8 -7]

User Allen Vork
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