平面直角坐标系中,O为坐标原点,已知两点A(1,2),B(-3,4),若点C满足 OC =α

2025-04-23 22:42:39
推荐回答(1个)
回答1:

设C(x,y),∵满足
OC
OA
OB
,其中α、β∈R且α+β=1,
OC
=α(1,2)+β(-3,4)
=(α-3β,2α+4β),
x=α-3β
y=2α+4β
α+β=1
,消去α,β得到x+2y-5=0.
故选D.