Question

a + b + C is equal to 9 and a b + BC + CA is equal to 23 then a square + b square + c square is equal to

Answer 1

It is given that a+b+c=9

So by using id (a+b+c) ^2= a^2+b^2+c^2+2ab+2bc+2ca

(9)^2=a^2+b^2+c^2+2(ab+bc+ca)

81=a^2+b^2+c^2+2×23

81-46=a^2+b^2+c^2

a^2+b^2+c^2=35