Question

If p + q = 5 and pq = 50, then find p2 + q2.

Answer 1

P+Q=5...........(1)

PQ=50...........(2)

(P+Q)^2=P^2+Q^2+2PQ

5^2=P^2+Q^2+2×50........from (1) and (2)

25=P^2+Q^2+100

P^2+Q^2= -75