| Exam Board | Edexcel |
|---|
| Module | C1 (Core Mathematics 1) |
|---|
| Topic | Quadratic Functions |
|---|
15. (a) By completing the square, find in terms of \(k\) the roots of the equation
$$x ^ { 2 } + 2 k x - 7 = 0$$
(b) Prove that, for all values of \(k\), the roots of \(x ^ { 2 } + 2 k x - 7 = 0\) are real and different.
(c) Given that \(k = \sqrt { } 2\), find the exact roots of the equation.
[0pt]
[P1 June 2002 Question 4]