Question

if p+q+r=7 and p^2+q^2+r^2=11. find pq+qr+rp. please answer me as early as you can......​

Answer 1

Step-by-step explanation:

hope it may help u....666.....

Answer 2

Answer:

19

Step-by-step explanation:

P+Q+R=7

LET THE SQUARE OF BOTH SIDE

(P+Q+R)^2 = 7^2

then expand equation like (a+b) ^2

p^2+q^2+r^2 + 2 ( pq + qr + rp) = 49

then put the value

11 + 2 ( pq + qr + rp) = 49

2 ( pq + qr + rp) = 49-11 = 38

pq + qr + rp = 38/2 = 19

pq + qr + rp = 19