# in this topic when we apply ele. row operation we write A = IA and for column A = AI . but we are confuse this concept . Can we write AAinverse = I for both the operation.

### Asked by jasbeer | 12th Apr, 2015, 02:17: AM

Expert Answer:

### A=IA=AI is always true for a matrix A and an identity matrix I.
So, we can use A =IA or A=AI as per convenience.
A^{-1}A=I is true for any matrix A. So we can write it for both the operations.

^{-1}A=I is true for any matrix A. So we can write it for both the operations.

### Answered by satyajit samal | 13th Apr, 2015, 06:11: PM

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