So sinboc: sinoac: sinaob = OA: 20b: 3oc.
So S△AOB:S△BOC:S△COA.
=(OA * OB * sinAOB):(OB * OC * sinBOC):(OA * OC * sinAOC)=(OA * OB * 3OC):(OB * OC * OA):(OA * OC * 2OB)= 3: 1:2
(2) Similarly, by using Lamy theorem, there are SINAOB: SINBOC: SINCOA = (n+m) OC: NOA: MOB.
So S△AOB:S△BOC:S△COA.
=(OA * OB * sinAOB):(OB * OC * sinBOC):(OA * OC * sin coa)=(OA * OB *(n+m)OC):(OB * OC * nOA):(OA * OC * mOB)=(n+m):n:m