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Vector u=ST has an initial point S(14,23) and terminal point T (5,19). Vector v=AB has an initial point A (7,17) and terminal point B(32,9). Part A: Write u and v in linear form. show all work. Part B: Find 4u-5v. Show all calculations. Part C: Given vector t=-16i+36j, use the dot product to determine if t and u are parallel, orthogonal, or neither. justify answer. Part D: Find another vector w that has the same relationship to vector t as vector u. justify.

User Mounesh
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Part A:
To find the linear form of a vector, we need to subtract the initial point from the terminal point to get the components of the vector.

Vector u:
Initial point S(14,23) and terminal point T (5,19)
u = T - S
u = (5 - 14, 19 - 23)
u = (-9, -4)
Linear form: u = -9i - 4j

Vector v:
Initial point A (7,17) and terminal point B(32,9)
v = B - A
v = (32 - 7, 9 - 17)
v = (25, -8)
Linear form: v = 25i - 8j

Part B:
4u-5v = 4(-9i - 4j) - 5(25i - 8j)
= (-36i - 16j) - (125i - 40j)
= -161i + 24j

Part C:
Given vector t = -16i + 36j

To determine if t and u are parallel, orthogonal, or neither, we need to find the dot product of t and u:
t · u = (-16)(-9) + (36)(-4)
t · u = 144
Since the dot product t · u is not equal to 0, t and u are not orthogonal. To determine if they are parallel, we need to find the magnitude of t and u:
|t| = sqrt((-16)^2 + (36)^2) = 40
|u| = sqrt((-9)^2 + (-4)^2) = sqrt(97)
The directions of the two vectors are not the same, so they are not parallel. Therefore, t and u are neither parallel nor orthogonal.

Part D:
To find another vector w that has the same relationship to vector t as vector u, we need to find a vector w that is parallel to u and has the same magnitude as t.

We know that vector u is not parallel to t, so we need to find the projection of t onto u to get a vector that is parallel to u and has the same direction as t. The projection of t onto u is given by:

proj_u t = (t · u / |u|^2) u

Substituting the values we have:

proj_u t = (t · u / |u|^2) u
= (144 / 97) (-9i - 4j)
= (-16.727)i - (7.818)j

This vector is parallel to u and has the same direction as t. To find a vector with the same magnitude as t, we just need to scale this vector:

w = (|t| / |proj_u t|) proj_u t
w = (40 / |proj_u t|) (-16.727i - 7.818j)
w = (-22.688i - 10.559j)

Therefore, vector w = -22.688i - 10.559j has the same relationship to vector t as vector u, in the sense that they have the same magnitude and are parallel.
User Wiika
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