Question 1

Paper 2, calculatorMedium7 marks

Let A(x)=(x+1)2−1A(x)=(x+1)^2-1 and B(x)=x(x+2)B(x)=x(x+2) where x∈Rx\in\mathbb{R}

(a)

Find A(3)A(3) and B(3)B(3)

[2]
(b)

Starting with A(x)A(x) show by a chain of algebraic equalities that A(x)A(x) has the same value as B(x)B(x) for every x∈Rx\in\mathbb{R}

[3]
(c)

Complete each statement using either == or ≡\equiv

A(3) □ B(3)A(3)\ \square\ B(3) A(x) □ B(x),for all x∈RA(x)\ \square\ B(x),\quad \text{for all }x\in\mathbb{R}
[2]

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