Question

*********************MEDAL AND FAN********************

Find parametric equations for the line which passes through P = (-8, 9, 4) and Q = (8, -6, -5)

Answer 1

It is a vector of 69

Answer 2

@Shrekinstine that makes no sense...

Answer 3

we have \(p+t(q-p)\)

Answer 4

so you have \(<-8,9,4>+t(<8,-6,-5>-<-8,9,4>) = <-8,9,4>+t<16,-15,-9>\)

Answer 5

with me?

Answer 6

\(<-8,9,4>+t(<8,-6,-5>-<-8,9,4>) =\\ <-8,9,4>+t<16,-15,-9>\)

Answer 7

F= a cost +a sin t + bt
x = a cos(t),
y = a sin(t),
z = bt,
and you have 2 equation with 2 unknowns.
http://en.wikipedia.org/wiki/Parametric_equation#3D_examples

Answer 8

this is 3d

Answer 9

@TomShoe do you follow?

Answer 10

\(<x,y,z>=<-8,9,4>+t<16,-15,-9>\)

so we have

\(x=-8+16t\\y=9-15t\\z=4-9t\)

Answer 11

@zzr0ck3r Mostly. You found a formula and are just plugging the values in. That's good so far, now I need to find x= , y=, and z=.

Answer 12

\(\uparrow\)

Answer 13

Did you have to find the magnitude?

Answer 14

@zzr0ck3r How did you convert each point into an equation with the variable t?

Answer 15

\(<\color{blue}{x},\color{red}{y},\color{green}{z}>=<\color{blue}{-8},\color{red}{9},\color{green}{4}>+t<\color{blue}{16},\color{red}{-15},\color{green}{-9}>\)

Answer 16

do you see?

Answer 17

\(\color{blue}{x = -8+16t}\)

Answer 18

Oh, I see. Thanks! Sorry for bugging you, just making sure I won't have to ask again :P

Answer 19

i much prefer people like you:)