1. The problem asks to explain exercise 75.2, but since the exact problem statement is not provided, I will demonstrate how to approach a typical algebraic exercise labeled similarly. 2. Usually, exercise 75.2 might involve solving an equation or simplifying an expression. Let's assume it is solving a quadratic equation of the form $$ax^2 + bx + c = 0$$. 3. The formula to solve quadratic equations is the quadratic formula: $$x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}$$ 4. Important rules: - The discriminant $$\Delta = b^2 - 4ac$$ determines the nature of the roots. - If $$\Delta > 0$$, two distinct real roots. - If $$\Delta = 0$$, one real root (double root). - If $$\Delta < 0$$, two complex roots. 5. To solve, identify $$a$$, $$b$$, and $$c$$ from the equation. 6. Calculate the discriminant $$\Delta$$. 7. Substitute values into the quadratic formula. 8. Simplify to find the roots. Since the exact problem is not given, this is a general explanation of how to solve a quadratic equation, which is a common type of problem in exercise sets like 75.2. If you provide the exact problem statement, I can give a detailed step-by-step solution.