List of formulae and tables of the normal distribution (MF9) 6. List of formulae and tables of the normal distribution (MF9) PURE MATHEMATICS Algebra For the quadratic equation ax2 + bx + c = 0: x= For an arithmetic series: u n = a + ^ n − 1 h d, S n = 12 n ^a + l h = 12 n "2a + ^n − 1h d , For a geometric series: u n = arn − 1, − b ! : ^b2 − 4ach 2a Sn = a ^1 − rnh ^r ! 1h, 1−r a ^ r < 1h S3 = 1 − r Binomial expansion: Kn O Kn O Kn O ^a + bhn = an + KK OO an − 1 b + KK OO an − 2 b2 + KK OO an − 3 b3 + g + bn, where n is a positive integer J N J N J N 1 2 3 L P L P L P JKn NO n! and KK OO = ^n − r h ! r ! r L P n ^n − 1h 2 n ^n − 1h^n − 2h 3 ^1 + xhn = 1 + nx + + x g, where n is rational and x < 1 2! x 3! Trigonometry Arc length of circle = ri ^i in radiansh Area of sector of circle = 12 r2 i ^i in radiansh sin i cos i 1 + tan2 i / sec2 i, tan i / cos2 i + sin2 i / 1. cot2 i + 1 / cosec2 i sin ^ A ! Bh / sin A cos B ! cos A sin B cos ^ A ! Bh / cos A cos B " sin A sin B A ! tan B tan ^ A ! Bh / 1tan " tan A tan B sin 2A / 2 sin A cos A 2 cos 2A / cos A − sin2 A / 2 cos2 A − 1 / 1 − 2 sin2 A tan 2A = 2 tan A 1 − tan2 A Principal values: − 12 r G sin−1 x G 12 r 0 G cos−1 x G r − 12 r < tan−1 x < 12 r 28 Cambridge International AS and A Level Mathematics 9709. Syllabus for examination in 2017 and 2018. List of formulae and tables of the normal distribution (MF9) Differentiation f^ xh xn 1n x ex sin x cos x tan x uv f l^ x h nxn–1 1 x ex cos x –sin x sec2 x u ddvx + v ddux v ddux − u ddvx u v v2 dy dy If x = f (t) and y = g (t) then dx = dt ' ddxt Integration f^ xh xn 1 x ex sin x cos x sec2 x y f (x) dx x n + 1 + c ^n ! − 1 h n+1 1n x + c ex + c – cos x + c sin x + c tan x + c y u ddvx dx = uv − y v ddux dx y ffl^^xxhh dx = 1n f^ xh + c Vectors If a = a1i + a2j + a3k and b = b1i + b2j + b3k then a.b = a1b1 + a2b2 + a3b3 = a b cos i Numerical integration Trapezium rule: b y f ^ xhdx . a 1 2 − h " y0 + 2 ^ y1 + y 2 + g + y n − 1h + y n ,, where h = b n a Cambridge International AS and A Level Mathematics 9709. Syllabus for examination in 2017 and 2018. 29 List of formulae and tables of the normal distribution (MF9) MECHANICS Uniformly accelerated motion v = u + at, s = 12 ^u + vh t, s = ut + 12 at2, v2 = u2 + 2as Motion of a projectile Equation of trajectory is: y = x tan i − Elastic strings and springs gx2 2V cos2 i T = mlx , 2 2 E = m2xl Motion in a circle For uniform circular motion, the acceleration is directed towards the centre and has magnitude v2 ~2 r or r Centres of mass of uniform bodies Triangular lamina: 2 3 along median from vertex Solid hemisphere of radius r: 83 r from centre Hemispherical shell of radius r: 12 r from centre Circular arc of radius r and angle 2a: r sin a a from centre Circular sector of radius r and angle 2a: 2r sin a 3a from centre Solid cone or pyramid of height h: 34 h from vertex 30 Cambridge International AS and A Level Mathematics 9709. Syllabus for examination in 2017 and 2018. List of formulae and tables of the normal distribution (MF9) PROBABILITY AND STATISTICS Summary statistics For ungrouped data: /x x= n , / ^ x − x h2 standard deviation = n = / x2 n −x2 For grouped data: / xf x= / , f / ^ x − x h2 f = /f standard deviation = Discrete random variables / x2 f 2 / f −x E ^ X h = / xp Var ^ X h = / x2 p − "E ^ X h, 2 For the binomial distribution B(n, p): JKn NO p r = KK OO pr ^1 − phn − r, r L P For the Poisson distribution Po(a): r p r = e−a ar! , n = np, v2 = np ^1 − ph n = a, v2 = a Continuous random variables E ^ X h = xf ^ x h dx y Var ^ X h = x2 f ^ x h dx − "E ^ X h, 2 y Sampling and testing Unbiased estimators: /x x= n , JK ^/ xh NO s2 = n 1− 1 K/ x2 − n O P L 2 Central Limit Theorem: v2 X + N ` n, n j Approximate distribution of sample proportion: JK p ^1 − phNO N K p, n OP L Cambridge International AS and A Level Mathematics 9709. Syllabus for examination in 2017 and 2018. 31 List of formulae and tables of the normal distribution (MF9) 32 Cambridge International AS and A Level Mathematics 9709. Syllabus for examination in 2017 and 2018.