Question

if a+b+c=9and ab+bc+ca=26 find a square+b square+c square​

Answer 1

Answer:

So, according to your question

a+b+c is given as 9 and ab+bc+ca is given as 26

and we have to find ! (a²+b²+c²)

here we will use the identity

(a+b+c)² = a²+b²+c²+2ab+2bc+2ca

and as (a+b+c) = 9

so, (a+b+c)² = (9)²

81 = a²+b²+c²+2ab+2bc+2ca

81 = a²+b²+c²+2(ab+bc+ca)

81 = a²+b²+c²+2(26)

81 = a²+b²+c²+52

a²+b²+c² = 81-52

a²+b²+c²= 29

So, the answer is 29