I’ve got a confusion. We know a 1x3 row matrix is a 3-vector i.e.(adsbygoogle = window.adsbygoogle || []).push({});

x= [ a b c]

Matrixxcan be written in vector notation likex= ai+ bj+ ck

wherei, j, kare unit vectors along x,y & z axes.

For dot product of

x.x= a^{2}+ b^{2}+ c^{2}whenx= ai+ bj+ ck

But according to the matrix multiplication rule, multiplication of two matrices is possible only when column of 1st matrix = row of the 2nd matrix.

Sox.x= [ a b c] [ a b c] is not possible

My questions are :

(1) Both x= [ a b c] and x= ai+ bj+ ckare same vector.

Then why this discrepancy happens?

(2) Does reallyx.xexist when x = [ a b c]? Can we approach in any other way to definex.xwhenx= [ a b c] ?

I’m novice at linear algebra. So it would be helpful for me if you can explain elaborately. I’m really at a loss about that confusion.

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# Confusion regarding dot product of vectors(row matrices)

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