Step 1: Apply Vieta's formulas for the given quadratic equation.
For the quadratic equation 2x2+bx+c=0, the sum of the roots (α+β) and the product of the roots (αβ) are given by:
α+β=−2b(1)
αβ=2c(2)
Step 2: Use the given condition α=2β in the sum of roots equation.
Substitute α=2β into equation (1):
2β+β=−2b