Answer:
The magnitude of the vertical component of vector u is 
The magnitude of the horizontal component of vector u is 
Step-by-step explanation:
A vector quantity has, a magnitude and a direction
The horizontal component of vector
is ║u║ cos α
The vertical component of vector
is ║u║ sin α
∵ The magnitude of vector u is 12 ft
∵ The measure of angle α is 135°
- Substitute the magnitude and the angle in the rule of
each component
∴
= 12 cos(135)
∴
= 12 sin(135)
∵ cos(135) = 
∴
= 12 (
)
∴
= 
- The magnitude of a number means the number without its sign
∴ The magnitude of the horizontal component of vector u is 
∵ sin(135) = 
∴
= 12 (
)
∴
= 
∴ The magnitude of the vertical component of vector u is 