f(x)=4x3+4x2−39x+36f(x) = 4x^3 + 4x^2 - 39x + 36f(x)=4x3+4x2−39x+36
Use the factor theorem to show that (x+4)(x + 4)(x+4) is a factor of f(x)f(x)f(x).
Hence, show that f(x)f(x)f(x) can be written in the form f(x)=(x+4)(ax+b)2f(x) = (x + 4)(ax + b)^2f(x)=(x+4)(ax+b)2, where a a\,a and b b\,b are integers to be found.
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.