延長線段AB到點C,使BC=2AB,在延長線段BA到點D,使AD=1/2AB,則AB:AC=___,CD:BD=___

延長線段AB到點C,使BC=2AB,在延長線段BA到點D,使AD=1/2AB,則AB:AC=___,CD:BD=___

延長線段AB到點C,使BC=2AB,在延長線段BA到點D,使AD=1/2AB,則AB:AC=___,CD:BD=___
D—A——B————C
AB:AC=1/3,
CD:BD=7/3