Algebra 4. ax2 + bx + c = ! ! √ √ −b + b2 − 4ac −b − b2 − 4ac a x− x− , 2a 2a 1. (a + b)2 = a2 + 2ab + b2 2. (a − b)2 = a2 − 2ab + b2 if b2 − 4ac ≥ 0 3. a2 − b2 = (a − b)(a + b) Trigonometry Hyperbolic functions Definitions Definitions sin x 1. tan x = cos x 2. cot x = cos x sin x e x − e −x 1. sinh x = 1 sin x 3. csch x = 1 sinh x 4. sech x = 1 cosh x 5. tanh x = sinh x cosh x 6. coth x = cosh x sinh x 4. csc x = Identities 2 1. cos2 x + sin2 x = 1 4. tan2 x + 1 = sec2 x Identities 2. sin 2x = 2 sin x cos x 5. cot2 x + 1 = csc2 x 1. cosh2 x − sinh2 x = 1 3. cos 2x = = cos2 x − sin2 x = 2 cos2 x − 1 = 1 − 2 sin2 x 6. tan 2x = 2 tan x 1 − tan2 x 2. 1 − tanh2 x = sech2 x 7. cot 2x = cot2 x − 1 2 cot x 3. coth2 x − 1 = csch2 x cos x 7. (arcsin x)0 = √ 2. (cos x)0 = − sin x 3. (tan x)0 = 0 sec2 x 2 1 1 − x2 8. (arccos x)0 = √ 4. (cot x) = − csc x 5. (sec x)0 = 2. cosh x = 2 4. sinh 2x = 2 sinh x cosh x 5. cosh 2x = = cosh2 x + sinh2 x = 2 cosh2 x − 1 = 2 sinh2 x + 1 Derivatives Derivatives 1. (sin x)0 = e x + e −x 1 3. sec x = cos x −1 1 − x2 tan x sec x 6. (csc x)0 = − cot x csc x 9. (arctan x)0 = 1 1 + x2 Integrals 1. R cos x dx = sin x 2. R sin x dx = − cos x 3. R sec2 x dx = tan x 4. R csc2 x dx = − cot x 5. R cot x dx = ln | sin x| 6. R tan x dx = = − ln | cos x| R 7. sec x dx = = ln | tan x + sec x| R 8. csc x dx = = − ln | cot x + csc x| 1. (sinh x)0 = cosh x 2. (cosh x)0 = sinh x 7. (arcsinh x)0 = 1 =√ 2 x +1 3. (tanh x)0 = sech2 x 4. (coth x)0 = − csch2 x 5. (sech x)0 = = − tanh x sech x 6. (csch x)0 = = − coth x csch x 8. (arccosh x)0 = 1 =√ 2 x −1 9. (arctanh x)0 = 1 = 2 x −1 Symmetry & Periodicity 1. sin(−x) = − sin(x) 5. cos(−x) = cos(x) 9. tan(−x) = − tan(x) 2. sin(x + π/2) = cos(x) 6. cos(x + π/2) = − sin(x) 10. tan(x + π/2) = − cot(x) 3. sin(x − π/2) = − cos(x) 7. cos(x − π/2) = sin(x) 11. tan(x − π/2) = − cot(x) 4. sin(x ± π) = − sin(x) 8. cos(x ± π) = − cos(x) 12. tan(x ± π) = tan(x) x −π −π/2 0 π/6 π/4 π/2 √1 2 π/3 √ 3 2 1 2π/3 √ 3 2 1 2 5π/6 π 3π/2 2π 1 2 0 −1 0 −1 0 1 sin(x) 0 −1 0 cos(x) −1 0 1 3 2 √1 2 1 2 0 − 12 tan(x) 0 – 0 √1 3 1 √ 3 – √ − 3 − √13 0 – – cot(x) – 0 – 1 − √13 √ − 3 – 0 1 √ √ 3 1 √1 3 √ − 3 2 Powers, Exponents & Logarithms 1. xa+b = xa · xb xa 2. xa−b = b x 1 3. x−a = a x 4. xa·b = (xa )b √ a 5. x /b = b xa 6. e x : (−∞, ∞) → (0, ∞) 9. ln(x) : (0, ∞) → (−∞, ∞) 10. ln(a · b) = ln(a) + ln(b) 7. e ln(x) =x 11. ln 8. ln(e x ) = x a b = ln(a) − ln(b) 12. ln(ab ) = b ln(a) Derivatives & Integrals 1. (xn )0 = nxn−1 0 3. (e ax ) = ae ax 5. (ln(x))0 = Z 6. Z 2. xn+1 x dx = , n 6= −1 n+1 n Z 4. Other Integrals Z 1 1 x 1. dx = arctan 2 2 x +a a |a| Z p 1 √ 2. dx = ln |x + x2 ± a2 | x2 ± a2 e ax dx = e ax a 1 x dx = ln(x) x Z 7. ln(x) dx = x ln(x) − x Inverse trigonometric functions √ arcsin x = arccos 1 − x2 y = arcsin(x) sin(y) x y = arccos(x) p 1 − x2 cos(y) p 1 − x2 x tan(y) cot(y) x √ 1 − x2 √ 1 − x2 x √ √ y = arctan(x) x −1 1 √ 1 + x2 √ x2 y = arccot(x) 1 1 + x2 x √ 2 x −1 √ 1 − x2 x x 1 x x 1 − x2 1 x x Inverse hyperbolic functions y = arcsinh(x) sinh(y) cosh(y) tanh(y) coth(y) x p y = arccosh(x) p x2 − 1 x2 + 1 x √ x2 + 1 √ x2 + 1 x y = arctanh(x) x √ 1 − x2 1 √ 1 − x2 y = arccoth(x) sign x √ x2 − 1 |x| √ x2 − 1 x2 − 1 x x 1 x x −1 1 x x x √ √ x2