Evaluate :

`a^2bc + b^2ca + c^2ab + a + b + c`

If ab + bc + ca = 0 , then the value of 1/(a^2 - bc) + 1/(b^2 - ca) + 1/(c^2 - ab) will be :

If a^(2) + b^(2) + c^(2) =ab + bc + ca find (a + c)/(b) = ?

If a + b + c = 13, a^2 + b^2 + c^2 = 69, " then find " ab + bc + ca .

If a= 297, b= 298, c= 299 and find a^(2) + b^(2) + c^(2) - ab - bc - ca ?

For real a, b and c if a^(2) + b^(2) + c^(2) = ab + bc + ca , then find the value of (a + b + c)^(2) A. 9a^(2) B. 81 a^(2) C. 27 a^(2) D. 24 a^(2)