(adsbygoogle = window.adsbygoogle || []).push({}); Determinant problem, matrices!! wee!

Hello everyone...

I got part a, and b, and i'm stuck on c...

Suppose that a 4 x 4 matrix A with rows v_1, v_2, v_3, and v_4 has determinant det A = -6. Find the following determinants determinants:

det[v_1 v_2 v_3 v_4 + 7*v_2]^T = ?

I made it Transposed so its more readable...really it is just

determinant of

v_1

v_2

v_3

v_4 + 7*v_2

I tried 7*-6 = -42 which was wrong, because if u multiply a column by a constant, it just mutlipies the matrix by that constant, but i don't know what happens if u multip[ly a constant to a a row, and then add it to another row..

Any ideas?

If ur confused on what i'm talking about, here is an answer to part a:

5*v_1

v_2

v_3

v_4

det of that matrix is: 5*-6 = -30;

and part b:

v_4

v_3

v_2

v_1

det of that matrix is 6, because if u swap rows, it will change the sign of the detemrinant.

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# Homework Help: Determinant problem, matrices wee!

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