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The number of all possible matrices of order 2 X 3 with each entry 1 or -1 is. :-

(1) 32. (2) 12

(3) 6. (4) 64

Plz give explanation also

ans is (4) 64

look, it is 2x3 matrix . so there would be 6 elements in all and each element has to be filled with either -1 or 1.

remeber fundamental priciple of multiplication taught in class 11.

i.e. acc. to this que. 6 elements can be filled in two posiible ways hence no. of ways would be 26 = 64

hope it helps

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acc. to me, it is (2) 12.

See, 2X3 = 2 rows 3 columns. Now lets start with1 at all places. that's (1st). Substitute all 1's by (-1)'s one by one, we get 6 more in which the last one has (-1) at all places. Right?? Soby now, 7 total. Now substitute back 1's in place of (-1)'s one by one, we get 5 more (Can't substitute 6 times becuz then it will become all 1's = the 1st Matrix). So 1+6+5 = 12 total.I'm sure this is the Answer, though if you really think try, maybe you can get more. Ok, acc. to this, min. Ans is 12 definitely 6 isn't the right option, plz check to confirm if more are possible.

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I also got 12 . but the answer given is 64.

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