Answer:
Step-by-step explanation:
given that U, V are two vectors in R^n
These two vectors can be written as a linear combination of 3 vectors
w1, w2, and w3
To prove that U+V also can be written as a linear combination of these three vectors.
Since U is a linear combination we can write for not all a,b, c equal to 0
[tex]U = aw1+bw2+cw3[/tex]
Similarly for d,e,f not all equal to 0
[tex]V= cw1+dw2+ew3[/tex]
Adding these we have
[tex]U+V =(a+d)w1 + (b+e) w2+(c+f)w3[/tex]
Here all a+d, b+e or c+f cannot be simultaneously 0.
So we get U+V can be written as a linear combination of w1, w2 w3 as follows:
[tex]U+W = gw1+hw2+iw3 \\g = a+d\\h = b+e\\i = c+f[/tex]
Proved