

InterviewSolution
Saved Bookmarks
1. |
Find X and Y, if(i) `X+Y=[[7, 0],[ 2, 5]]`and `X-Y=[[3, 0],[ 0 ,3]]`(ii) `2X+3Y=[[2, 3],[ 4, 0]]`and `3X+2Y=[[2,-2],[-1, 5]]` |
Answer» (i) `X+Y = [[7,0],[2,5]]->(1)` `X-Y = [[3,0],[0,3]]->(2)` Adding (1) and (2), `=> 2X = [[10,0],[2,8]]` `=>X = [[5,0],[1,4]]` `:. Y = [[7,0],[2,5]] - [[5,0],[1,4]]` `=> y = [[2,0],[1,1]]` (ii) `2X+3Y = [[2,3],[4,0]]->(1)` `3X+2Y = [[2,-2],[-1,5]] ->(2)` Multiplying (1) by `3` and (2) by `2` and then subtracting, `6X+9Y-6X-4Y = [[6,9],[12,0]] - [[4,-4],[-2,10]]` `=>5Y = [[2,13],[14,-10]] ` `=>Y = [[2/5,13/5],[14/5,-2]] ` Now, `3X+2Y = [[2,-2],[-1,5]]` `=>X = 1/3([[2,-2],[-1,5]] - 2 [[2/5,13/5],[14/5,-2]])` `=X = 1/3[[6/5,-36/5],[-33/5,12]]` `=X = [[2/5,-12/5],[-11/5,4]].` |
|