Question

将一副三角尺按如图叠放,则△AOB于△DOC的面积之比等于

Answer 1

在AOB中,tan30°=OA/OB = √3/3

OA=√3OB/3

△AOB的面积S1 = (1/2)OA*OB = √3*OB²/6

在COD中,tan30°=OC/OD = √3

OD=√3*OC

△COD的面积S2 = (1/2)OC*OD = √3*OC²/2

OB = OC

S1:S2 = √3*OB²/6 :√3*OC²/2

＝1／6　：1/2

= 1:3