Prove that for all real values of xxx:
x2+6x>2x−5 x^2 + 6x > 2x - 5 x2+6x>2x−5"If I add 3 to a number and then square the sum, the result is greater than the square of the original number."
State, giving a reason, if the above statement is always true, sometimes true or never true.
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.