Subtraction of vector Some judgment question vector ab - vector BC = vector AC, seeking advice vector ab - vector BC should be wrong, but I can't work it out. I'm depressed

Subtraction of vector Some judgment question vector ab - vector BC = vector AC, seeking advice vector ab - vector BC should be wrong, but I can't work it out. I'm depressed

Vector AB + vector BC = vector AC, vector ab - vector BC = vector AB + vector CB