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November 01, 2025, 10:28:52 am

Author Topic: QUESTIONNN MATRICES?  (Read 785 times)  Share 

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physics

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QUESTIONNN MATRICES?
« on: October 29, 2010, 10:15:39 pm »
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The order of matrix A is 3*2 and the number of columns of matrix B is 3.
If the results of A(B+C) is a 3*3 matrix then the order of matrix C must be?
A. 2X3
B.3x2
C.2x2
D.3x3
E.1x3

well i SAID
 since A=3x2 and B= zx3 and resulting matrix must be 3x3 meaning C has to be yx3 but in order for B and C to be able  to be added y=3 so that there can be in correct order blah blah. what i dont get is how
the answer is 2x3!!!!!!!!!!!!
oh wait is it because addition has to have the same order
BUT

multipplaction needs the same mxn=nxz or something/
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Re: QUESTIONNN MATRICES?
« Reply #1 on: October 29, 2010, 10:18:56 pm »
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I don't do further but i'm pretty sure it's the same concept as methods?
For multiplication to be possible, the number of columns of matrix 1 has to be the same as number of rows of matrix 2.
Thus if matrix A is 3*2, then (B+C) has to be 2*?, the ? is a 3 since they told you.
You can only add B and C if they have the same dimensions.
And they even told you the result of multiplication is a 3*3 matrix, so matrix A has to be 3*? and matrix (B+C) has to be ?*3
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mojomojo

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Re: QUESTIONNN MATRICES?
« Reply #2 on: October 29, 2010, 10:36:35 pm »
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The answer should be A?

The result is 3x3 and matrix A is 3x2... Therefore the product of (B+C) must be 2x3 in order to make a 3x3, and only matrix with the same order can be added/subtracted with each other.. so it should be 2x3.
« Last Edit: October 29, 2010, 10:43:57 pm by mojomojo »
It's all over now..

gold104

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Re: QUESTIONNN MATRICES?
« Reply #3 on: October 29, 2010, 10:55:55 pm »
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The answer should be A?

The result is 3x3 and matrix A is 3x2... Therefore the product of (B+C) must be 2x3 in order to make a 3x3, and only matrix with the same order can be added/subtracted with each other.. so it should be 2x3.

I also believe its A..

TyErd

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Re: QUESTIONNN MATRICES?
« Reply #4 on: October 30, 2010, 10:06:58 am »
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yup its A
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