CHEATSHEET MATH1110 Scalar projection v in direction of w Mathematics 1 vw = University of Newcastle 1 Properties of Scalar Triple v·w |w| [u, v, w] = −[u, w, v] = −[v, u, w] [u, v, w] = [v, w, u] = [w, u, v] Vector projection v in direction of w Vectors vw = Length of a vector |v| = p x2 + y 2 + z 2 v·w |w|2 [λu, v, w] = λ[u, v, w] w 2 Triple Products x(t) = a + pt y(t) = b + qt z(t) = c + rt u × (v × w) v · w = vx wx + vy wy + vz wz = |v||w|cosθ Scalar Triple Basic Properties of Dot Product [u, v, w] = u · (v × w) v · v = ||v||2 v×w v·w =w·v u · (v + w) = u · v + u · w y−b z−c x−a = = p q r Vector Equation of a Line w r(t) = d + tv v Cross Product î v × w = vx wx Symmetric Form of Line Equation V = [u, v, w] u (λv) · w = λ(v · w) = v · (λw) Lines in 3D Parametric Equation of a Line Vector Triple Scalar (Dot) Product [(a + b), v, w] = [a, v, w] + [b, v, w] ĵ vy wy k̂ vz wz Volume of a parallelpiped 3 Properties of Triple Products Cartesian Equation of a Plane (u · v)w 6= u(v · w) Basic Properties of Cross Product Planes in 3D ax + by + cz = d u · (v × w) = (u × v) · w u × v = −v × u u · (v × w) = v · (w × u) = w · (u × v) u × (v + w) = u × v + u × w u × (v × w) 6= (u × v) × w λ(v × w) = (λv) × w = v × (λw) u × (v × w) = (u · w)v − (u · v)w Parametric Equation of a Plane x(u, v) = a + pu + lv y(u, v) = b + qu + mv z(u, v) = c + ru + nv 1 Lear nyourunicour s ei noneday.Checkspoonf eedme. com f orf r eevi deosummar i es,not esandcheatsheet sbyt ops t udent s . CHEATSHEET Vector Equation of a Plane n · (r − d) = 0 Distance of Point From Plane d= |n · P0 P1 | ||n|| Angle Between Planes cos θ = 4 n1 · n2 ||n1 ||||n2 || Complex Numbers z = a + ib Where: i2 = −1 Properties of Modulus and Conjugate |zw| = |z||w| 5 Trigonometry Angle Sum Formulae z |z| w |w| sin(θ + φ) = sin θ cos φ + sin φ cos θ cos(θ + φ) = cos θ cos φ − sin θ sin φ |z + w| ≤ |z| + |w| tan(θ + φ) = |z − w| ≥ |z| − |w| tan θ + tan φ 1 − tan θ tan φ z±w =z±w Pythagorean Identity zw = zw cos2 x + sin2 x = 1 Polar Form z = rcisθ = r(cos θ + i sin θ) Where r is the modulus ||z|| and θ the argument arg z . 6 Hyperbolic tions Trigonometric Func- Polar Form Operations and Properties rcis(θ) × pcis(φ) = rpcis(θ + φ) Modulus |z| = p a2 + b2 y=0.5 r rcis(θ) = cis(θ − φ) pcis(φ) p arg(zw) = arg(z) + arg(w) z = arg(z) − arg(w) arg w Conjugate If z = a + ib then Euler’s Formula cosh(x) = ex + e−x 2 sinh(x) = ex − e−x 2 eix = cos x + i sin x z = z − ib Where e is Euler’s Number and x is real. De Moivre’s Theorem Given z = reiθ : n n inθ z =r e tanh x = sinh x) cosh x 2 Lear nyourunicour s ei noneday.Checkspoonf eedme. com f orf r eevi deosummar i es,not esandcheatsheet sbyt ops t udent s . CHEATSHEET Properties of Hyperbolic Functions 2 9 Inverse Trigonometric Functions 2 cosh x − sinh x = 1 cosh(x + y) = cosh x cosh y + sinh x sinh y π 2π π 2 3π 2 sinh(x − y) = sinh x cosh y − sinh y cosh x tanh x + tanh y 1 + tanh x tanh y −0.5 0.5 − Function Composition Power Function π 2 π 2 −1 −0.5 y = arcsin x 0.5 y = arccos x (g ◦ f )(x) = g(f (x)) 1 d[xn ] = nxn−1 dx Addition Rule d[u(x) + v(x)] = u0 (x) + v 0 (x) dx π 2 8 d[kf (x)] = kf 0 (x) dx 1 −π 7 Scalar Multiple π −1 tanh(x + y) = Rules for Differentiation Logarithms Product Rule −3 −2 −1 Basic Properties 1 − 2 3 π 2 loga 1 = 0 Quotient Rule loga a = 1 loga xy = loga x + loga y loga x = loga x − loga y y loga xn = n loga x y = arctan x If f (x) = 10 Differentiation ax = bx logb a loga x = logb x logb a u(x) then: v(x) f 0 (x) = Average Rate of Change Of f (x) over the interval [x1 , x2 ]: Change of Base d[u(x)v(x)] = u(x)v 0 (x) + u0 (x)v(x) dx f (x2 ) − f (x1 ) Avg. rate of change = x2 − x1 v(x)u0 (x) − u(x)v 0 (x) [v(x)]2 Chain Rule If f (x) = u[v(x)] then: f 0 (x) = v 0 (x)u0 (x) First Principles That is: Derivative of f (x) with respect to x at x = a: df du df = dx du dx dy f (a + h) − f (a) = lim dx h→a h 3 Lear nyourunicour s ei noneday.Checkspoonf eedme. com f orf r eevi deosummar i es,not esandcheatsheet sbyt ops t udent s . CHEATSHEET Exponential Function x d[e ] = ex dx Integration Stationary Points Lower Riemann Sum Formula Over interval [a, b] with n rectangles: Concavity 1 d[ln x] = for x > 0 dx x A= • f 00 (x) > 0: Concave up - local minimum • f 00 (x) < 0: Concave down - local maximum Trig Functions d[cos x] = − sin x dx Point of Inflection n X f (xk )∆x k=1 Where: ∆x = b−a n Integral as Riemann Summ f 00 (x) = 0 b Z f (x) dx = lim 11 Hyperbolic Functions d[sinh x] = cosh x dx 1 d[tanh x] = dx cosh2 x 12 f 0 (x) = 0 Logarithmic Functions d[sin x] = cos x dx d[tan x] = sec2 x dx Derivative Tests d[cosh x] = − sinh x dx Inverse Trig Functions d[arcsin x] 1 =√ for − 1 < x < 1 dx 1 − x2 d[arccos x] −1 =√ for − 1 < x < 1 dx 1 − x2 1 d[arctan x] = dx 1 + x2 Linear Approximations Linearisation at a Point Linearisation of f (x) at x = a is given: 0 L(x) = f (a)(x − a) + f (a) n→∞ a Where: ∆x = n X f (xk )∆x k=1 b−a n Fundamental Theorem of Calculus Given f is continuous over [a, b] Z x f (u) du then F 0 (x) = f (x) Small Change Formula 1. If F (x) = Change in a function value ∆f when perturbed by a small amount ∆x is: 2. If G(x) is any antiderivative of f (x) then: a ∆f ≈ f 0 (a)∆x Z b f (x) dx = G(b) − G(a) a Integration By Substitution Z I= Z f (x) dx = f (x(u)) dx du du 4 Lear nyourunicour s ei noneday.Checkspoonf eedme. com f orf r eevi deosummar i es,not esandcheatsheet sbyt ops t udent s . CHEATSHEET Integration By Parts Z Z u dv = uv − v du Standard Integrals Z xn+1 + C (n 6= −1) xn dx = n+1 Z cos x dx = sin x + C Z sin x dx = − cos x + C Z 2 sec x dx = − tan x + C Z x x e dx = e + C Z 1 dx = loge (x) + C x Z cosh x dx = sinh x + C Trapezoidal Rule 14 ∆x {f (x0 ) + 2f (x1 ) + ... + 2f (xn−1 + f (xn )} 2 b−a Where: ∆x = n Force Simpson’s Rule Where: Tn = b−a Where: ∆x = n 13 Volumes Z 1 dx = arctan x + C 1 + x2 A is area of object d is depth F = ρgd A Of Revolution x-Axis Rotation b Z π(f (x))2 dx a sinh x dx = cosh x + C 1 dx = arcsin x + C 1 − x2 g is gravitational acceleration (≈ 9.8) P = V = √ ρ is density Pressure Z Z F = ρgAd ∆x {f (x0 ) + 4f (x1 ) + 2f (x2 ) + ... + 4f (xn−1 ) + f (xn )} 3 ∆x = {f (x0 ) + 4[Sum of odds] + 2[Sum of evens] + ... 3 ... + f (xn )} Sn = Applications: Hydrostatic Pressure and Force y-Axis Rotation b Z V = 2πxf (x) dx a By Slices Z V = b A(x) dx a Where: A(x) is the cross-sectional area. 5 Lear nyourunicour s ei noneday.Checkspoonf eedme. com f orf r eevi deosummar i es,not esandcheatsheet sbyt ops t udent s .