Q1. Prove that the sum of any two sides of a triangle is greater than the third side. Q2. Prove that if two sides of a triangle are unequal, the angle opposite to the longer side is smaller.. Created by Dasham10. Math

Question no 1...Let ABC be a triangleWe can extend BA past A into a straight line.There exists a point D such that DA=CA.Therefore, from Isosceles Triangle has Two Equal Angles:∠ADC=∠ACDThus by Euclid's fifth common notion:∠BCD>∠BDCSince △DCB is a triangle having ∠BCDgreater than ∠BDC, this means that BD>BC.But:BD=BA+ADand:AD=ACThus:BA+AC>BCA similar argument shows that AC+BC>BA and BA+BC>AC