Find the values of a and b for which


Given :


To find : a and b


Formula used :



Where cij = ai1b1j + ai2b2j + ai3b3j + ……………… + ainbnj


If A is a matrix of order a b and B is a matrix of order c d ,then matrix AB exists and is of order a d ,if and only if b = c


=


= = =


=


Equating similar terms,


2a – b = 5


-2a – 2b = 4


Adding the above two equations,we get


-3b = 9


b = = -3


b = -3


substituting b = -3 in 2a – b = 5,we get


2a + 3 = 5


2a = 5 – 3 = 2


a = 1


a = 1 and b = -3


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