I'm stuck with a problem which is, I believe, simple, but I can't solve it by myself.
So, I have 4 vectors a,b,c,d that are linearly independent. I am supposed to check whether the following vectors are dependent or independent:
a1 = a+2c+d
b1 = 2a-b+c
c1 = a+c+d
Thank you in advance. :D