Unit 4 Flashcards
A vector is perpendicular/orthogonal if…
the dot product = 0
A vector is parallel if…
a1/a2 = b1/b2
What is the formula for rectangular coordinates to polar?
X = r * cos theta Y = r * sin theta
Modulus, magnitude, hypotenuse, radius
All the same. ||V||
What is the formula for polar coordinates to rectangular?
R = root(x^2+y^2) Theta = arctan (y/x)
What is the interval when in polar coordinates?
between 0 and 2pi, must also be in the same quadrant.
What are complex numbers in rectangular form?
a+bi
What are complex numbers in polar form?
r(cos theta + i sin theta)
What is the formula for magnitude of a vector?
root(a^2+b^2)
What is the formula for a unit vector?
(1/||v||)*<a,b>
When finding the nth root, what is K?
K is n-1
When finding the nth root, what is N?
N is the root number
What is the formula for finding the nth root?
Zk = ^n root(r)[cos (theta+2piK)/n + i sin (theta+2piK)/n]
What is DeMoivre’s theorem formula?
(a+bi)^2 = r^n[cos (thetan)+isin (thetan)]
What is the formula for finding the angle between two vectors?
arccos ([vw]/||v||||w||) = theta
What is the formula for a vector V projected onto W?
ProjwV = ([vw]/||w||^2)w
What is the formula for finding work done?
W = F * D
When finding work formula, what is F?
F is a force vector
What is F denoted by in a work calculation?
force number*(cos theta)i+forcenumber(sin theta)j
When finding work formula, what is D?
D is a distance vector
What is D denoted by in a work calculation?
<x2-x1,y2-y1>
What is a parametric equation?
An equation that models the travel of an object or projectile
What is the formula for X in a parametric equation?
X = Vo (cos theta)t + Xo
What is the formula for Y in a parametric equation?
Y = -1/2 * gt^2+(VoSin theta)*t + Yo
What does X represent in a parametric equation?
X is horizontal distance
What does Y represent in a parametric equation?
Y is vertical position
What is the velocity of gravity in both forms?
g = 32 ft/sec^2 g = 9.8 m/sec^2
What does g represent in a parametric equation?
gravity
What does Xo represent in a parametric equation?
Starting X position
What does Yo represent in a parametric equation?
Starting Y position
What does Vo represent in a parametric equation?
Starting velocity
What does t represent in a parametric equation?
Time
What does theta represent in a parametric equation?
Starting angle (for example, the angle at which a ball is thrown)
What does “eliminating a parameter” refer to?
Removing t from the curved graph via substitution and solving.
How do you convert degrees to radians?
Multiply the degree measure by pi/180
How do you convert radians to degrees?
Multiply the radian by 180/pi
How do you find arc length?
s = r * theta (s = arc length, r = radius of circle, theta = angle of the arc)