New FP2 1. Paper 3 (a) Sketch, on the same axes, the graphs with equation y = 2x – 3, and the line with equation y = 5x – 1. (2) (b) Solve the inequality 2x – 3 < 5x – 1. 2. (3) (a) Use the substitution y = vx to transform the equation d y (4 x y)( x y) = ,x>0 dx x2 (I) into the equation x dv = (2 + v)2. dx (II) (b) Solve the differential equation II to find v as a function of x. (4) (5) (c) Hence show that y = 2x x , where c is an arbitrary constant, ln x c is a general solution of the differential equation I. 3. (1) (a) Find the value of for which x cos 3x is a particular integral of the differential equation d2 y + 9y = 12 sin 3x. dx 2 (4) (b) Hence find the general solution of this differential equation. The particular solution of the differential equation for which y = 1 and (4) dy = 2 at x = 0, is y = g(x). dx (c) Find g(x). (4) (d) Sketch the graph of y = g(x), 0 x . (2) 4. Figure 1 Figure 1 shows a sketch of the cardioid C with equation r = a(1 + cos ), < . Also shown are the tangents to C that are parallel and perpendicular to the initial line. These tangents form a rectangle WXYZ. (a) Find the area of the finite region, shaded in Fig. 1, bounded by the curve C. (6) (b) Find the polar coordinates of the points A and B where WZ touches the curve C. (5) (c) Hence find the length of WX. (2) Given that the length of WZ is 3 3a , 2 (d) find the area of the rectangle WXYZ. (1) A heart-shape is modelled by the cardioid C, where a = 10 cm. The heart shape is cut from the rectangular card WXYZ, shown in Fig. 1. (e) Find a numerical value for the area of card wasted in making this heart shape. (2) n 5. Prove by the method of differences that r r 1 6. 1n dn x 2 ( e cos x ) 2 Given that ex cos (x + dx n 1 4 2 = 1 6 n(n + 1)(2n + 1), n > 1. (6) n), n 1, find the Maclaurin series expansion of ex cos x, in ascending powers of x, up to and including the term in x4. (3) 7. The transformation T from the complex z-plane to the complex w-plane is given by w= z 1 , zi z i. (a) Show that T maps points on the half-line arg(z) = in the z-plane into points on the circle 4 w = 1 in the w-plane. (4) (b) Find the image under T in the w-plane of the circle z = 1 in the z-plane. (6) (c) Sketch on separate diagrams the circle z = 1 in the z-plane and its image under T in the w-plane. (2) (d) Mark on your sketches the point P, where z = i, and its image Q under T in the w-plane. 8. (2) Solve the equation z5 = i, giving your answers in the form cos + i sin . (5) The End