Limit Rules of differentiation lim[ f ( x) ⋅ g ( x)] = lim f ( x) ⋅ lim g ( x) = L1 ⋅ L2 ; x→a x→a x→a f ( x) L f ( x) lim lim = x→a = 1 x→ a g ( x ) lim g ( x) L2 L2 ≠ 0 d u ( )= dx v x→a ∞ xr x2 x3 x e = lim1 + = 1 + x + + + = ∑ n →∞ 2 ! 3! n r =0 r ! n x n 1 lim1 + = e n →∞ n lim θ →0 sin θ θ ex − 1 =1 = 1 lim x →0 x First principal f ' ( x) = lim ∆x → 0 f (x + ∆x ) − f (x ) ∆x n! r!(n − r )! C =C n r Prn = (n − r )! C +C n r n n−r n r +1 =C n +1 r +1 ( x + y) = n x n + C1n x n −1 y + C2n x n − 2 y 2 + ... + Cnn−1 xy n −1 + y n S1: General term; S2, Solve for r Trigonometry sin (A ± B) = sin A cos B ± cos A sin B cos (A ± B) = cos A cos B sin A sin B 2 sin A cos B = sin (A + B) + sin (A − B) 2 cos A cos B = cos (A + B) + cos (A − B) 2 sin A sin B = cos (A − B) − cos (A + B) tan (A ± B) = sin 2 x = tan A ± tan B 1 tan A tan B 1 − cos 2 x 1 + cos 2 x cos 2 x = 2 2 tan 2 x + 1 = sec 2 x cot 2 x + 1 = csc 2 x v S1: Set f’(x)=0; => x=1,5,or 7 First D Test x x<1 x=1 1<x<5 x=5 5<x<7 x=7 7<x dy/dx +ve 0 -ve 0 +ve 0 +ve Maximum value: f(1) Maximum point: (1,f(1)) Minimum value: f(5) Maximum point: (5,f(5)) Stationary point:(7,f(7)) du dv −u dx dx v2 Chain Rule dy dy du = ⋅ dx du dx -----Differentiation ---> Normal : y − y1 = − 1 ( x − x1 ) f ′( x1 ) d n ( x ) = nx n −1 dx Tangent : y − y1 = f ' ( x)( x − x1 ) d (sin x) = cos x dx Second D Test f”(xo)<0 f”(xo)>0 d (sec x) = sec x tan x dx d (cos x) = − sin x dx d (cot x) = − csc 2 x dx d (csc x) = − csc x cot x dx d x (e ) = e x dx d (ln sec x + tan x ) = sec x dx <--- Integration ----- dv d 2 s ds a= = dt dt 2 dt S1: formulate equation i.e. ∫ udv = uv − ∫ vdu v= dA d (4πr 2 ) dr = dt dr dt S3: Substitutes and solve. i.e. Application of Integration b ; Area= a dv du ∫ u dx dx = uv − ∫ v dx dx b xe − > d (e ); x cos x − > d (sin x) x ∫ (high − low)dx x ∫ (2πR) Hdy Shell method: a x2 ); 2 e x cos x − > d (e x ); x ln x − > d ( b b a a Vol = ∫ 2πxydx or ∫ 2πxydy *Use by part X2 or Recurrent (vertical->dx; horizontal ->dy) Integration Trigo-Sub S1’ set f’(x)=0 => x= xo S2’check f”(xo) If f”(xo)<0 , (xo, f”(xo)) is a max. pt. If f”(xo)>0 , (xo, f”(xo)) is a min. pt. a2 − x2 Point of Inflexion ∫ ∫ ∫ f”(xo) changes signs Assymptotes e.g. y = 2 x − 3 + 2 [x + 5] Vertical: x = −5 Horizontal/Oblique: y = 2 x − 3 put x = a sin a 2 + x 2 , put x = a tan ∫ d 1 (ln x) = dx x d (ln sec x ) = tan x dx Integration by parts Integration d x a = a x ln a dx 1 d log a x = dx x ln a Rate of Change, A = 4πr 2 S2: apply chain rule to diff w.r.t t. d (tan x) = sec 2 x dx The Binomial Theorem C rn = d dv du (uv) = u +v dx dx dx Application of Differentiation Tangent and Normal ∫ ∫ ∫ ∫ a a f ( x)dx = ∫ f (t )dt , a x 2 − a 2 , put x = a sec a a a f ( x)dx = − ∫ f ( x)dx , a a b kf ( x)dx = k ∫ f ( x)dx , a b a [ f ( x) ± g ( x)]dx b a b a a −a ∫ πR 2 dh a b b b Disc method: f ( x)dx = 0 , a b b f ( x)dx ± ∫ g ( x)dx a c b a c f ( x)dx = ∫ f ( x)dx + ∫ f ( x)dx 2 a f ( x ) dx even f ( x )dx = ∫ 0 0 odd M.I. When n=1, … It is true for n=1. Assume the statement is true for n=k i.e. … When n=k+1 … It is true for n=k+1 By the principle of mathematical induction, …. b Vol = ∫ πx dy b 2 a or Vol = ∫ πy 2 dx a Matrix Properties of Matrices Operation Properties of Determinants det AT = det A. A0 = 0A = 0 det AB = (det A)(det B). a11 a12 a21 a22 a13 a23 = a 11 A(BC) = (AB)C a31 a32 a33 A(B ± C) = AB ± AC a21 a22 a31 a32 (αA)(βB) = A(αβ)B = (αβ)AB (A + B)T = AT + BT (AB)T = BTAT . A11 1 A = adj A12 A A 13 A21 A22 A23 −1 A31 A32 A33 n -1 (b)(AB)-1 = B-1A-1 , -1 A) -1 n (e) (A ) = (A ) Area of ABCD = AB × AD 1 AB × AD 2 Volume of Parallel pine = (b × c) • a Area of ABD= 1 (b × c) • a 2 1 Volume of tetrahedron = (b × c ) • a 6 Pyramid with parallelogram base = 1 (b × c) • a 3 a33 2. b1 b2 b3 c1 a1 b1 c2 = − a3 b3 c3 a2 b2 b1 b2 kb3 c1 c2 kc3 b3 c3 a1 + ka2 b1 + kb2 c1 + kc2 c3 = a2 b2 c2 c2 a3 b3 c3 c1 a1 a1 a3 b1 b1 b3 c1 x y c2 + a2 b2 z c2 c3 c3 and a3 b3 a3 b3 c1 c1 = 0 c3 (3) a ⋅ b = a ⋅ c ⇒ b = c Or | OP | = x 2 + y 2 + z 2 | OP |= x 2 + y 2 If OP ≠ 0, sin θ = cos θ = 4. x x2 + y2 y x + y2 2 , tan θ = and and then a ⋅ b = x2i + y2j + z2k , b = x1x2 + y1y2 + z1z2 cos θ = y , x The unit vector in the direction of a is x1 x 2 + y 1 y 2 + z 1z 2 a⋅b = 2 a b x1 + y 1 2 + z1 2 ⋅ x 2 2 + y 2 2 + z 2 2 If a ⋅ b = 0 ,a is perpendicular to b. a . Vector Products a a × b=|a||b|sin θ n, where θ is the angle between a and b and n a11x + a12 y + a13z = b1 a 21x + a 22 y + a 23z = b 2 a x + a y + a z = b 32 33 3 31 5. mi + nj = xi + yj ⇒ m=x 6. mi + nj = 0 ⇒ m=n=0 7. a is a unit vector iff a = 1 . and n=y is the unit vector (a) a × a = 0 (b) a × b = –b × a (c) k(a × b) = (ka) × b = a × (kb) . 1 Cramer’s Rule 1.Parallelism (d) |a × b| = |b × a| ∆ x determinant of A with x column replaced If the vectors p = mi + nj and q = xi + yj are parallel, then (e) For non-zero vectors a and b , a × b = 0 if and only if a x y x m = = and m n y n and b are parallel. 2. Division of a Line Segment (h) |a × b|2 = |a|2|b|2 – (a ⋅ b)2 AB such that AP : PB = m : n, then Vectors in R3 ∆y ∆x ∆ , y= , z= z ; det A det A det A 2 Gaussian Elimination x= Application of Vectors: Volume of triangular prism = a31 (2) i ⋅ j = j ⋅ k = k ⋅ i = 0. OP = xi + y j + zk. + a 13 System of Linear Equation -1 -1 A = a33 Or – a 12 a21 a23 3. a1 det A = a2 a3 a3 (Properties of inverses) (c) (AT)-1 = (A-1)T , (d) ( a32 a1 + x b1 + y c1 + z a1 b1 a2 b2 c2 = a2 b2 Non-singular => det A ≠ 0 (a) (A-1)-1 = A, a23 (1) i ⋅ i = j ⋅ j = k ⋅ k = 1. If a = x1i + y1j + z1k a1 k det A = a2 ka3 Inverse of Matrix a22 Scalar product(Dot Product) a ⋅ b = | a || b |cos θ, where θ is the angle between a and b. OP = xi + yj. 1. AI = IA = A (A± B)C = AC ± BC Vectors 1 a b e reduce to echelon form. 0 1 d f 0 0 1 g mQB + nQA m+n n m a+ b , i.e. p = n+m m+n QP = 3. Use inverse of Matrix AX = B If det A ≠ 0, Unique Solution and −1 X=A B *For Homogeneous AX=0 , If det A ≠ 0, then X =0, trivial solution. If det A = 0, AX = B has ∞ or no solutions (use Gaussian Elimination to Solve) (i) 3. Coplanar Vol=0 => Scalar Triple Product =0 c = x3i + y3 j + z3k then (ii) i × j = k , k × j = –i i × k = –j) , j×k=i (iii) If a × b = a × c y1 y2 y3 , k × i = j. (j × i = –k ⇒ b ≠c (e.g. a and b are parallel, and c is 0). Scalar Triple Product (b × c) • a If a = x1i + y1 j + z1k , b = x2i + y2 j + z2k and x1 a ⋅ (b × c) = x2 x3 i × i = j × j = k × k = 0. If a = x1i + y1 j + z1k and b = x2 i + y 2 j + z 2k are two non-zero vectors, and θ is the angle between them, then z1 z2 . z3 i a × b = a b sin θ nˆ = x1 x2 j y1 y2 k z1 . z2 ,