Matrices and Determinants HELP!

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Question

Matrices and Determinants HELP!

http://i729.photobucket.com/albums/ww292/akatushi101/matriceeeeee.jpg

phi · Answer

These problems are not too complicated.  2A means multiply every entry in A by 2
adding 2 matrices means add corresponding locations.  For example, add row 1, col 1 of A to row 1, col 1 of B and so on.

So to do 2A+2B,   multiply every entry in A by 2,  multiply every entry in B by 2  and then add the two matrices that you get.
Or
because 2A+2B= 2(A+B),   first add A to B, then multiply the result by 2 (in every position)

anonymous · Answer

Okay...im confused on the first one, which of the choices are correct?

phi · Answer

Are you saying you do not know how to multiply by 2????

anonymous · Answer

2) choice4

anonymous · Answer

3) choice 1