8. Vectors

Find the force required to keep a 3000-lb car parked on a hill that makes an angle of 15° with the horizontal.

In Exercises 39–46, find the unit vector that has the same direction as the vector v.

v = 6i

A force of 176 lb makes an angle of 78° 50′ with a second force. The resultant of the two forces makes an angle of 41° 10′ with the first force. Find the magnitudes of the second force and of the resultant.

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Two forces act on a point in the plane. The angle between the two forces is given. Find the magnitude of the resultant force.

forces of 116 and 139 lb, forming an angle of 140° 50′

In Exercises 1–4, u and v have the same direction. In each exercise: Find ||u||.

In Exercises 1–4, u and v have the same direction. In each exercise: Find ||v||.