Given that k k\,k is a positive constant,
Prove that for positive values of a a\,a and bbb
kab+4ba≥4k \frac{ka}{b} + \frac{4b}{a} \geq 4\sqrt{k} bka+a4b≥4kProve, by counter example, that this is not true for all values of a a\,a and bbb.
257 exam-style questions on Edexcel A Level Maths Algebraic Methods, covering 7.1 Algebraic Fractions, 7.2 Dividing Polynomials, 7.3 The Factor Theorem, 7.4 Mathematical Proof, and 7.5 Methods of Proof. Each one has a worked solution and a mark scheme showing where the marks go.