Chapter 8.4-8.7 Test formulas Flashcards
Vector
A quantity that has magnitude and direction and is a directed line segment
Vectors in standard form- position vector
V= P1 P2=
Unit vector in 2d and 3d
U= v/||v||; ||u||=1
Algebraic Vector in 2d
V= ||v|| cosθi + ||v|| sinθj
Dot Product in 2d
v⋅w= a1a2 + b1b2
Angle between vectors in 2d and 3d
cosθ= u⋅v/ ||u|| ||v||
What does orthogonal mean?
Perpendicular and the dot product is 0
What if two vectors have the same slopes?
They are parallel
Work formula if no angle in 2d
W= ||F|| ⋅ ||vectorAB||
Work formula if angle in 2d
W= F ⋅ vector AB
Distance formula in space (3d)
d= √(Δx)^2 +(Δy)^2 +(Δz)^2
Δ (delta) means what?
change in the variable
Position Vectors in Space (3d)
V= P1P2= (x2-x1)i + (y2-y1)j + (z2-z1)k
Dot Product in space (3d)
v⋅w= a1a2+ b1b2+ c1c2
Is the dot product a value or an equation
a value
General Form for a Circle in 2d
Standard form= (x-h)^2+ (y-k)^2= r^2. Center: (h,k). radius= r
General form for a sphere
(x-x0)^2+ (y-y0)^2+ (z-z0)^2 =r^2. Center: (x0, y0, z0). Radius= r
Direction Angles of a 3 dimensional vector
cos α= a/ ||v||; cos β= b/ ||v||; cos γ= c/ ||v||
For cross product (VxW) what do you use?
Matrices
What is (uxv) ⋅ u?
0
What is the difference between (vxw) and (wxv)?
Their answers will be opposite