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If \(\begin{bmatrix}2x+1 & 5x \\[0.3em]0 & y^2+1 \\[0.3em]\end{bmatrix}\) = \(\begin{bmatrix}x+3 & 10 \\[0.3em]0 & 26 \\[0.3em]\end{bmatrix},\)find the value of (x + y). |
Answer» Given two matrices are equal. \(\begin{bmatrix}2x+1 & 5x \\[0.3em]0 & y^2+1 \\[0.3em]\end{bmatrix}\) = \(\begin{bmatrix}x+3 & 10 \\[0.3em]0 & 26 \\[0.3em]\end{bmatrix}\) We know that if two matrices are equal then the elements of each matrices are also equal. ∴2x + 1 = x + 3 … (1) ⇒ 2x – x = 3 – 1 ⇒ x = 2 And 5x = 10 … (2) y2 + 1 = 2 … (3) ⇒ y2 = 26 – 1 ⇒ y2 = 25 ⇒ y = 5 or – 5 ∴ x = 2, y = 5 or – 5 ∴ x + y = 2 + 5 = 7 Or x + y = 2 – 5 = – 3 |
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