Solution:-
Given : PSR is a triangle.and PQ = PR
To prove:- PS>PQ
Proof :
In △PQR,
PQ=PR
∴∠PQR=∠PRQ(∵Angles opposite to equal sides are equal)
Now,
∠PQR>∠PSQ(∵ exterior angle of a triangle is always greater than each of its interior angles.)
⇒∠PRQ>∠PSQ(∵∠PQR=∠PRQ)
⇒∠PRS>∠PSR
now in △PSR,
∠PRS>∠PSR
∴PS>PR
⇒PS>PQ(∵PQ=PR)
Hence proved.