Prove that, for all real values of xxx,
x2+4x+12>x+3x^2 + 4x + 12 > x + 3x2+4x+12>x+3
[4]
Markscheme
1.4.3 Completing the square for a quadratic curve Questions
8 exam-style questions on OCR (MEI) A Level Maths 1.4.3 Completing the square for a quadratic curve. Each one has a worked solution and a mark scheme showing where the marks go.