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In the given figure, the incircle of ABCtouches the sides BC, CA and AB at P, Q andRrespectively. Prove that(AR + BP+CQ) = (AQ + BR+CP)= half of (perimeter of ABC). |
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Answer» Answer: As SEEN in the figure:- AR=AQ (tangents from a point to a circle are always equal in LENGTH)......................(i) BP =BR (tangent from point B to circle...so...BP same in LENGTH as BR)..............(ii) CQ=CP ( similar REASON)..............(iii) ----------- adding the 3 equations:- (lhs=rhs) AR+BP+CQ=AQ+BR+CP From the figure we can see that:- perimeter=AC+CB+BA Further breaking this equation:- =(AQ+QC)+(CP+PB)+(BR+RA) =》2(AQ+BR+CP)=2(AR+BP+CQ)= Perimeter [from(i),(ii), (iii)] therefore, (AQ+BR+CP)=(AR+BP+CQ)= ½ (PERIMETER)
HENCE PROVED |
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