1. Examples
1. Solve linear equations x+y=2 and 2x+3y=4 using Inverse matrix Method
Solution: Here `x+y=2` `2x+3y=4`
Now converting given equations into matrix form `[[1,1],[2,3]] [[x],[y]]=[[2],[4]]`
Now, A = `[[1,1],[2,3]]`, X = `[[x],[y]]` and B = `[[2],[4]]`
`:.AX = B`
`:.X = A^-1 B`
`=1 × 3 - 1 × 2`
`=3 -2`
`=1`
`"Here, " |A| = 1 != 0`
`:. A^(-1) " is possible."`
`"Now, "A^(-1)=1/|A| × Adj(A)`
`"Here, "X = A^(-1) × B`
`:. X = 1/|A| × Adj(A) × B`
`:.[[x],[y]]=[[2],[0]]`
`:.x=2,y=0`
2. Solve linear equations 2x+7y-11=0 and 3x-y-5=0 using Inverse matrix Method
Solution: Here `2x+7y-11=0` `3x-y-5=0`
Now converting given equations into matrix form `[[2,7],[3,-1]] [[x],[y]]=[[11],[5]]`
Now, A = `[[2,7],[3,-1]]`, X = `[[x],[y]]` and B = `[[11],[5]]`
`:.AX = B`
`:.X = A^-1 B`
`=2 × (-1) - 7 × 3`
`=-2 -21`
`=-23`
`"Here, " |A| = -23 != 0`
`:. A^(-1) " is possible."`
= | | `+(-1)` | `-(3)` | | | `-(7)` | `+(2)` | |
| T |
|
`"Now, "A^(-1)=1/|A| × Adj(A)`
`"Here, "X = A^(-1) × B`
`:. X = 1/|A| × Adj(A) × B`
`:.[[x],[y]]=[[2],[1]]`
`:.x=2,y=1`
3. Solve linear equations 3x-y=3 and 7x+2y=20 using Inverse matrix Method
Solution: Here `3x-y=3` `7x+2y=20`
Now converting given equations into matrix form `[[3,-1],[7,2]] [[x],[y]]=[[3],[20]]`
Now, A = `[[3,-1],[7,2]]`, X = `[[x],[y]]` and B = `[[3],[20]]`
`:.AX = B`
`:.X = A^-1 B`
`=3 × 2 - (-1) × 7`
`=6 +7`
`=13`
`"Here, " |A| = 13 != 0`
`:. A^(-1) " is possible."`
= | | `+(2)` | `-(7)` | | | `-(-1)` | `+(3)` | |
| T |
|
`"Now, "A^(-1)=1/|A| × Adj(A)`
`"Here, "X = A^(-1) × B`
`:. X = 1/|A| × Adj(A) × B`
`:.[[x],[y]]=[[2],[3]]`
`:.x=2,y=3`
4. Solve linear equations 2x-y=11 and 5x+4y=1 using Inverse matrix Method
Solution: Here `2x-y=11` `5x+4y=1`
Now converting given equations into matrix form `[[2,-1],[5,4]] [[x],[y]]=[[11],[1]]`
Now, A = `[[2,-1],[5,4]]`, X = `[[x],[y]]` and B = `[[11],[1]]`
`:.AX = B`
`:.X = A^-1 B`
`=2 × 4 - (-1) × 5`
`=8 +5`
`=13`
`"Here, " |A| = 13 != 0`
`:. A^(-1) " is possible."`
= | | `+(4)` | `-(5)` | | | `-(-1)` | `+(2)` | |
| T |
|
`"Now, "A^(-1)=1/|A| × Adj(A)`
`"Here, "X = A^(-1) × B`
`:. X = 1/|A| × Adj(A) × B`
`:.[[x],[y]]=[[45/13],[-53/13]]`
`:.x=45/13,y=-53/13`
This material is intended as a summary. Use your textbook for detail explanation. Any bug, improvement, feedback then
|