Quadratic Equal Roots 5D7F31
1. **State the problem:** Find the smallest value of $p$ for which the quadratic equation $$x^2 - 2(p+1)x + p^2 = 0$$ has real and equal roots. Then find the roots of the quadratic equation.
2. **Recall the condition for real and equal roots:** A quadratic equation $$ax^2 + bx + c = 0$$ has real and equal roots if its discriminant $$\Delta = b^2 - 4ac = 0$$.
3. **Identify coefficients:** Here, $$a = 1$$, $$b = -2(p+1)$$, and $$c = p^2$$.
4. **Set the discriminant to zero:**
$$\Delta = [-2(p+1)]^2 - 4(1)(p^2) = 0$$
5. **Simplify the discriminant:**
$$4(p+1)^2 - 4p^2 = 0$$
Divide both sides by 4:
$$(p+1)^2 - p^2 = 0$$
6. **Expand and simplify:**
$$(p^2 + 2p + 1) - p^2 = 0$$
$$2p + 1 = 0$$
7. **Solve for $p$:**
$$2p = -1$$
$$p = -\frac{1}{2}$$
8. **Find the roots for $p = -\frac{1}{2}$:** Substitute back into the quadratic:
$$x^2 - 2\left(-\frac{1}{2} + 1\right)x + \left(-\frac{1}{2}\right)^2 = 0$$
Calculate inside the parentheses:
$$-2\left(\frac{1}{2}\right)x + \frac{1}{4} = 0$$
Simplify:
$$x^2 - x + \frac{1}{4} = 0$$
9. **Since roots are equal, root is:**
$$x = \frac{-b}{2a} = \frac{-(-1)}{2(1)} = \frac{1}{2}$$
**Final answer:**
- Smallest value of $p$ is $-\frac{1}{2}$.
- The roots are both $\frac{1}{2}$.