Find the vector and parametric equations for the line through the point P=(−3,2,−1)

and the point Q=(0,−1,1)
.

Vector Form: r=⟨
,
, -1 ⟩+t⟨

,
, 2 ⟩

Parametric form (parameter t
, and passing through P
when t=0
):

x=x(t)=


y=y(t)=


z=z(t)=

1 answer

To find the vector equation for the line through point P=(-3, 2, -1) and Q=(0, -1, 1), we can use the formula:

r = P + t(Q - P)

where r is the position vector of a point on the line, t is a parameter, and P and Q are the given points.

Substituting the values, we have:

r = <-3, 2, -1> + t(<0, -1, 1> - <-3, 2, -1>)

Simplifying:

r = <-3, 2, -1> + t(<0 - (-3), -1 - 2, 1 - (-1)>)
= <-3, 2, -1> + t(<3, -3, 2>)
= <-3 + 3t, 2 - 3t, -1 + 2t>

Therefore, the vector form of the line is:

r = <-3 + 3t, 2 - 3t, -1 + 2t>

For the parametric equations, we can express x(t), y(t), and z(t) in terms of the parameter t:

x(t) = -3 + 3t
y(t) = 2 - 3t
z(t) = -1 + 2t

Therefore, the parametric equations for the line passing through P when t=0 are:

x = -3 + 3t
y = 2 - 3t
z = -1 + 2t