Relationship between Unequal Sides of Triangle and the Angles Opposite to It.
In a Δ ABC,...
Question
In a ΔABC,IfAC>AB and the bisector of ∠A meets BC at E, then
A
CE>BE
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
B
CE<BE
No worries! We‘ve got your back. Try BYJU‘S free classes today!
C
CD>BE
No worries! We‘ve got your back. Try BYJU‘S free classes today!
D
CD<BE
No worries! We‘ve got your back. Try BYJU‘S free classes today!
Open in App
Solution
The correct option is ACE>BE Given△ABC,AC>AB.ThebisectorofAmeetsBCatE.Construction:TakeapointFonAC,suchthatAF=AB.JoinBFandEF.LetBFintersectAEatO.△ABFisanisoscelestriangle(SinceAB=AF,byconstruction)AEbisects∠A(given)∴AEistheperpendicularbisectorofBF,soanypointonAEisequidistantfromBandF.Inparticular,BE=FESo,in△BEF,∠EBF=∠EFB=α,(anglesoppositeequalsides)So,∠BEO=90=∠FEO(Letangle=γ)ThusAEalsobisects∠BEF.Now,becauseinatriangle,exteriorangleisthesumofinterioroppositeangles,so∠EFC=θ+γandex∠B=θ+γSo,∠EFC=ext∠B.But∠B=2θ+∠C,so∠EFC=2θ+∠C.∴∠EFC>∠CSo,CE>FE⇒CE>BE(SinceBE+FE)