Solving Equations Involving A⁻¹, B⁻¹ and C⁻¹

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To solve the equations involving A⁻¹, B⁻¹, and C⁻¹, the following approaches were discussed. For the equation AX = C, the solution is X = A⁻¹C. In the case of AXB = C, the solution is X = A⁻¹CB⁻¹. For BXA = C + B, the solution is X = B⁻¹(C + B)A⁻¹. Lastly, for XABC = D, the solution is X = B⁻¹C⁻¹D. The importance of the order of matrix multiplication was emphasized throughout the discussion.
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Given that A^-1 , B^-1 and C^-1 exist, solve the following equations for X:

a)AX=C
b)AXB=C
c)BXA=C+B
d)XABC=D

plse help...
 
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fazal said:
Given that A^-1 , B^-1 and C^-1 exist, solve the following equations for X:

a)AX=C
b)AXB=C
c)BXA=C+B
d)XABC=D

plse help...
a) Multiply both sides of the equation on the left by A-1:
A-1AX= X= A-1C.
b) Multiply both sides of the equation on the left by A-1 and on the right by B-1:
A-1AXBB-1= X= A-1CB-1

Can you try c and d now?
 
so
c) X=(C+B)A^-1B^-1

d)X=B^-1C^-1D

plse check thks
 
c)BXA=C+B

Therefore XA = B^(-1)(C+B) therefore X = B^(-1)(C+B)A^(-1)

Remember matrix multiplication is NOT commutative.

Do the same steps for d), note ORDER MATTERS
 
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