If α and β are the roots of $2x^2-5x+3=0$, then α² + β² equals:

α + β = 5/2 and αβ = 3/2. So α² + β² = $(\alpha +\beta {)}^2-2$αβ = 25/4 − 3 = 13/4. (The roots are 1 and 3/2, and 1 + 9/4 = 13/4.)