设AB=a(向量),AC=b,
AP=AM+tMC=2a/3+t(b-2a/3)=(2/3)(1-t)a+tb
AP=AN+sNB=sa+(3/5)(1-s)b.
s=(2/3)(1-t),t=(3/5)(1-s),消去s,得到t=1/3.
AP=4a/9+b/3=(4/9)AB+(1/3)AC.
设AB=a(向量),AC=b,
AP=AM+tMC=2a/3+t(b-2a/3)=(2/3)(1-t)a+tb
AP=AN+sNB=sa+(3/5)(1-s)b.
s=(2/3)(1-t),t=(3/5)(1-s),消去s,得到t=1/3.
AP=4a/9+b/3=(4/9)AB+(1/3)AC.