A ship is sailing due north. At a certain point the bearing of a lighthouse 12.5 km away is N 38.8° E. Later on, the captain notices that the bearing of the lighthouse has become S 44.2° E. How far did the ship travel between the two observations of the lighthouse?
Ch. 7 - Applications of Trigonometry and Vectors
Chapter 8, Problem 34
Given u = 〈-2, 5〉 and v = 〈4, 3〉, find each of the following.
v - u
Verified step by step guidance1
Identify the given vectors: \( \mathbf{u} = \langle -2, 5 \rangle \) and \( \mathbf{v} = \langle 4, 3 \rangle \).
Recall that vector subtraction \( \mathbf{v} - \mathbf{u} \) is performed component-wise: subtract the corresponding components of \( \mathbf{u} \) from \( \mathbf{v} \).
Set up the subtraction for each component: \( (v_x - u_x, v_y - u_y) \), where \( v_x = 4, u_x = -2, v_y = 3, u_y = 5 \).
Calculate each component difference separately: \( 4 - (-2) \) for the x-component and \( 3 - 5 \) for the y-component.
Combine the results to write the vector \( \mathbf{v} - \mathbf{u} \) as \( \langle 4 - (-2), 3 - 5 \rangle \).

Verified video answer for a similar problem:
This video solution was recommended by our tutors as helpful for the problem above.
Was this helpful?
Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Vector Representation
Vectors are quantities defined by both magnitude and direction, often represented as ordered pairs or tuples in two dimensions. For example, u = 〈-2, 5〉 indicates a vector with components -2 along the x-axis and 5 along the y-axis.
Recommended video:
Introduction to Vectors
Vector Subtraction
Vector subtraction involves subtracting corresponding components of two vectors. For vectors v = 〈v₁, v₂〉 and u = 〈u₁, u₂〉, the difference v - u is 〈v₁ - u₁, v₂ - u₂〉, resulting in a new vector.
Recommended video:
Adding Vectors Geometrically
Component-wise Operations
Operations on vectors such as addition and subtraction are performed component-wise, meaning each component is handled independently. This simplifies calculations and helps visualize vector operations geometrically.
Recommended video:
Algebraic Operations on Vectors
Related Practice
Textbook Question
Textbook Question
Two forces of 128 lb and 253 lb act on a point. The resultant force is 320 lb. Find the angle between the forces.
4
views
Textbook Question
To determine the distance RS across a deep canyon, Rhonda lays off a distance TR = 582 yd. She then finds that T = 32° 50' and R = 102° 20'. Find RS. See the figure.
<IMAGE>
Textbook Question
Apply the law of sines to the following:
A = 104°, a = 26.8, b = 31.3.
What happens when we try to find the measure of angle B using a calculator?
1
views
Textbook Question
Two forces of 692 newtons and 423 newtons act on a point. The resultant force is 786 newtons. Find the angle between the forces.
1
views
Textbook Question
Without using the law of sines, explain why no triangle ABC can exist that satisfies A = 103° 20', a = 14.6 ft, b = 20.4 ft.
5
views
