Question

已知向量a＝（3,2）向量b＝（－1,2）向量c＝（4,1）若向量a＝m向量b+n向量c求实数m,n的值

Answer 1

a = mb + nc

(3,2) = m(-1,2) + n(4,1)

(3,2) = (-m + 4n,2m + n)

∴ -m + 4n = 3,2m + n = 2

联立方程得 m = 5/9,n = 8/9