Question

If I is a unit matrix of order 2 and M + 4I = `[(8, -3),(4, 2)]`, the matrix M is ______.

विकल्प

• `[(4, 3),(4, -2)]`

• `[(4, 3),(4, 2)]`

• `[(4, -3),(-4, 2)]`

• `[(4, -3),(4, -2)]`

Answer 1

If I is a unit matrix of order 2 and M + 4I = `[(8, -3),(4, 2)]`, the matrix M is `underlinebb([(4, -3),(4, -2)])`.

Explanation:

Given M + 4I = `[(8, -3),(4, 2)]`

∴ M = `[(8, -3),(4, 2)] - 4I`

= `[(8, -3),(4, 2)] - 4[(1, 0),(0, 1)]`

= `[(8, -3),(4, 2)] - [(4, 0),(0, 4)]`

= `[(8 - 4, -3 - 0),(4 - 0, 2 - 4)]`

= `[(4, -3),(4, -2)]`