Question

dados os vetores w=(5,1), v=(2,1), w=(1,-1), determine os numeros a e b tais que w= au+ bv

Answer 1

(1,-1)=a(5,1)+b(2,1)

1=5a+2b  (i)
-1=a+b   vezes 5  ==>-5=5a+5b (ii)


(i)-(ii)

6=-3b  ==>b=-2
-1=a+b  ==>-1=a-2  ==>a=1