=1 T≡y=mx±√2m2+4 ‌‌‌‌‌‌↓(√2,2√2−2) ⇒(2√2−2−m√2)=±√2m2+4 ⇒2m2−2m√2(2√2−2)+4(3−2√2)=2m2+4 ⇒−2√2m(2√2−2)=4−12+8√2 ⇒−4√2m(√2−1)=8(√2−1) ⇒m=−√2‌ and ‌m→∞ ∴ Tangents are x=√2 and y=−√2x+√8 ∴P(√2,0) and Q(1,√2) and S=(0,−√2) ∴(PS)2+(QS)2=4+9=13