MATHEMATICS
1. It is given that f(x) = (2x − 5)3 + x, for x ∈ R . Show that f is an increasing function.
2. (i) In the expression (1− px)6 , p is a non-zero constant. Find the first three terms when (1− px)6 is expanded in ascending powers of x.
(ii) It is given that the coefficient of x2 in the expansion of (1−x)(1− px)66 is zero. Find the value of p .
3.
In the diagram, OAB is a sector of a circle with centre O and radius 8 cm. Angle BOA is α radians. OAC is a semicircle with diameter OA. The area of the semicircle OAC is twice the area of the sector OAB.
(i) Find α in terms of Π.
(ii) Find the perimeter of the complete figure in terms of Π.
4 The third term of a geometric progression is −108 and the sixth term is 32. Find
(i) the common ratio,
(ii) the first term,
(iii) the sum to infinity.
5. (i) Show that (sin Θ / (sin Θ + cos Θ)) + (cos Θ (sin Θ − cos Θ) Ξ (1 / (sin2Θ− cos2Θ)).
(ii) Hence solve the equation (sin Θ / (sin Θ + cos Θ)) + (cos Θ (sin Θ − cos Θ)= 3, for 0° ≤ Θ ≤ 360°.
6. Relative to an origin O, the position vectors of three points, A, B and C, are given by
where p and q are constants.
(i) Show that (OA)→ is perpendicular to (OC)→ for all non-zero values of p and q.
(ii) Find the magnitude of (CA)→ in terms of p and q.
(iii) For the case where p = 3 and q = 2, find the unit vector parallel to (BA)→.
7. A curve has equation y = x2 − 4x + 4 and a line has equation y = mx, where m is a constant.
(i) For the case where m = 1, the curve and the line intersect at the points A and B. Find the coordinates of the mid-point of AB.
(ii) Find the non-zero value of m for which the line is a tangent to the curve, and find the coordinates of the point where the tangent touches the curve.
8. (i) Express 2x2 − 12x + 13 in the form a(x + b)2 + c, where a, b and c are constants.
(ii) The function f is defined by f(x)= 2x2 − 12x + 13 for x ≥ k, where k is a constant. It is given that f is a one-one function. State the smallest possible value of k.
The value of k is now given to be 7.
(iii) Find the range of f.
(iv) Find an expression for f−1 x and state the domain of f−1 .
9. A curve has equation y = fx and is such that f′ x = 3x 1/2 + 3x−1/2 − 10.
(i) By using the substitution u = x 1/2, or otherwise, find the values of x for which the curve y = f(x) has stationary points.
(ii) Find f′′(x) and hence, or otherwise, determine the nature of each stationary point.
(iii) It is given that the curve y = fx passes through the point (4,−7).
10.
The diagram shows part of the curve y = (x− 2)4 and the point A1, 1 on the curve. The tangent at A cuts the x-axis at B and the normal at A cuts the y-axis at C.
(i) Find the coordinates of B and C.
(ii) Find the distance AC, giving your answer in the form (√a/b), where a and b are integers.
(iii) Find the area of the shaded region.