Formulas and Equations Flashcards
Parametric equation of a line
x = x0 + at
y= y0 + bt
z= z0 + ct
(know how to get all of these equal by setting them equal to T)
Vector equation of a line
r= r0 + at
Equation of a plane
a(x-x0) + b(y-y0) + c(z-z0) = 0
property of Normal vectors of planes :
n1 x n2 = 0
the angle between two planes
cos (x) = (n1 * n2) / |n1||n2|
distance from a point to a plane
|(n * v)/ |n||
What makes a function continuous (lim)?
lim r(t) = r(t0)
velocity
r’(t)
acceleration
v’(t) = r’‘(t)
speed
|r’(t)|
arc length
INTEG( a_> b) |r’(t)| dt
Unit Tangent vector (T’(t))
r’(t)/ |r’(t)|
Unit Normal Vector (N(t))
T’(t)/ |T’(t)|
Binormal Unit vector (B(t) )
T(t) x N(t)
parametric eqts of normal line
x = x0 + fx (t)
y= y0 + fy (t)
z= z0 + fz(t)
Unit vector projection
GRADIENT ( f) * n
Max unit vector projection
|GRADIENT f(x,y,z) |
Min unit vector projection
- |GRADIENT f(x,y,z)|
Second Deriv test
(fx2)(fy2) - (fxy)^2
What if the second deriv is negative?
saddle point
What constitutes a local maximum?
Second partial Deriv < 0
What constitutes a local Min?
Second Partial Deriv > 0
Lagrange
F= GRAD( f) - Lambda (GRAD g)
surface area
DBL INTEG |fu x fv| dudv
What are cylindrical coordinated similar to
polar coordinates
Spherical coordinates
x= rcos (t) sin(p)
y = rsin(t)sin(p)
z= rcos (p)
r^2 = x^2 + y^2 + z^2
R= row, t= theta, p= phi
line integral
INTEG F * dr = F(r(t)) * r’(t) dt
When is a line integral path independent?
INTEG F* dr = 0
Fundamental theorem of line integrals
INTEG(a ->b) F(r(t)) * r’(t) dt = P(r(b) - r(a))
Greens Thm
INTEG Mdx +Ndy = DBL INTEG( Nx - My) dxdy
div F
GRADIENT * F
curl F
GRADIENT x F
When is a parameterized surface smooth?
Partial ders - > ru x rv = 0
unit normal vector
(ru x rv) / |ru x rv|
vector-valued differential of surface
dS= (ru x rv)dudv
surface integral
DBL INTEG f(r(u,v)) |ru x rv|dudv
Stokes Thm
DBL INTEG (GRADIENT x F) * dS = INTEG F * dr
Divergence thm
TRP INTEG (GRAD * F(x,y,z) dV = DBL INTEG F*dS
Assumptions of stokes thm
S must be a positively oriented piecewise smooth surface with a simple closed piecewise smooth boundary curve. (F has cont partial deriv)
Assumptions of Divergence thm
Let E be a simple solid region, S be a boundary surface of E with an outward (positive) orientation. (F has cont partial deriv)