We are asked to find: \(x^2+y^2\), for \(x\) and \(y\) are the roots of the equation.
\(3x^2+4x+12\) has a sum of \(\frac{-4}{3}.\)
\(3x^2+4x+12\) has a product of \(\frac{12}{3}=4.\)
Use the manipulation:\((x+y)^2-2(xy)=x^2+y^2\).
Thus, the answer is \((\frac{-4}{3})^2-2(4)=\frac{16}{9}-\frac{72}{9}=\frac{-56}{9}.\)
By Vieta....
We have the form Ax^2 + Bx + C = 0
Let the roots be R1 and R2
The sum of these = -B/A = -4/3 = R1 + R2 (1)
And the product of these = C/A = = 12/3 = 4 = R1*R2 which implies that 8 = 2*R1*R2
Square (1) and we get that
R1^2 + 2*R1*R2 + R2^2 = 16/9
R1^2 + 8 + R2^2 = 16/9
R1^2 + 72/9 + R2^2 = 16/9 subtract 72/9 from both sides
R1^2 + R2^2 = 16/9 - 72/9 = -56/9