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Hello students.
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Today we will discuss about this question.
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In this question we are given that a 2 cross 2 matrix that is a that is equals to a11, a12, a2 and a2.
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And the adjoint of a joint of a is given by d that is equals to a2 minus a2 -12 minus a -21 a -1 -1.
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We need to prove that here, da that is equal to a -2 -2 -a -2.
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To ad that is equal to determinant of a multiplied by i and again we need to prove that determinant of a that is equal to the determinant of d so here first of all we need to prove that the part a after we will need after we will prove the part b so here first of all we will find d a so that is equals to in matrix a 2 to 2 minus a12 minus a21a21 a1 multiplied with a1a1, a2, a21, a21, a222.
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So that is equal to we will get a222a2a1 minus a12 a2a2 -1 minus a211a2 -1 plus a11a1a2 then a22222222 -a2 -2 -2 minus a2 a12, a21 plus a11 a222.
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So here we can say that that is equal to we will get a22a21 minus a12 a2a2 -0.
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A -1 -a -1 -2 -2 -a -2 -1.
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So that will be suppose equation 1.
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Now again we will find ad that is equal to a11 -1.
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A12, a2, a2 multiplied with d, that is a2 minus a212 minus a21a21a1a1.
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So that is equal to we will get a111a2 minus a12a1a2 minus a11a12 plus a11a1a12 a2.
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A22 minus a22 -2 minus a21a2 minus a22 -2 minus a2 -2 a21, a12 plus a11a22...