Find the set of values of a a\,a for which the equation ax2+8x+2=0ax^2 + 8x + 2 = 0ax2+8x+2=0 has no real roots.
211 exam-style questions on Edexcel A Level Maths Quadratics, covering 2.1 Solving Quadratics, 2.2 Completing the Square, 2.3 Sketching Quadratic Graphs, 2.4 The Discriminant, and 2.5 Modelling with Quadratics. Each one has a worked solution and a mark scheme showing where the marks go.