**Vectors Problem Explanation** --- **Given:** - \( u = 1i - 3j \) - \( v = 2i + 3j \) **Tasks:** a) Calculate \( 2(u) - 3(v) \) \[ 2(1i - 3j) - 3(2i + 3j) \] \[ = (2i - 6j) - (6i + 9j) \] \[ = 2i - 6j - 6i - 9j \] \[ = -4i - 15j \] b) Calculate \( (i - 3j) \cdot (2i + 3j) \) - This involves finding the dot product: The dot product is calculated as: \[ (1 \cdot 2) + (-3 \cdot 3) = 2 - 9 = -7 \] c) Find a unit vector in the same direction as \( v \) - To find a unit vector, divide each component of \( v \) by its magnitude. - First, calculate the magnitude of \( v \): \[ \|v\| = \sqrt{2^2 + 3^2} = \sqrt{4 + 9} = \sqrt{13} \] - The unit vector in the direction of \( v \) is: \[ \frac{1}{\sqrt{13}}(2i + 3j) = \left(\frac{2}{\sqrt{13}}i + \frac{3}{\sqrt{13}}j\right) \] --- This set of problems helps understand vector arithmetic and operations such as scaling, subtraction, and dot product, as well as finding unit vectors.

Trigonometry (11th Edition)
11th Edition
ISBN:9780134217437
Author:Margaret L. Lial, John Hornsby, David I. Schneider, Callie Daniels
Publisher:Margaret L. Lial, John Hornsby, David I. Schneider, Callie Daniels
Chapter1: Trigonometric Functions
Section: Chapter Questions
Problem 1RE: 1. Give the measures of the complement and the supplement of an angle measuring 35°.
icon
Related questions
Question

Hi I just need help with b & c 

**Vectors Problem Explanation**

---

**Given:**

- \( u = 1i - 3j \)
- \( v = 2i + 3j \)

**Tasks:**

a) Calculate \( 2(u) - 3(v) \)

   \[
   2(1i - 3j) - 3(2i + 3j)
   \]

   \[
   = (2i - 6j) - (6i + 9j)
   \]

   \[
   = 2i - 6j - 6i - 9j
   \]

   \[
   = -4i - 15j
   \]

b) Calculate \( (i - 3j) \cdot (2i + 3j) \)

   - This involves finding the dot product:

     The dot product is calculated as:

     \[
     (1 \cdot 2) + (-3 \cdot 3) = 2 - 9 = -7
     \]

c) Find a unit vector in the same direction as \( v \)

- To find a unit vector, divide each component of \( v \) by its magnitude.

- First, calculate the magnitude of \( v \):
  
  \[
  \|v\| = \sqrt{2^2 + 3^2} = \sqrt{4 + 9} = \sqrt{13}
  \]

- The unit vector in the direction of \( v \) is:

  \[
  \frac{1}{\sqrt{13}}(2i + 3j) = \left(\frac{2}{\sqrt{13}}i + \frac{3}{\sqrt{13}}j\right)
  \]

---

This set of problems helps understand vector arithmetic and operations such as scaling, subtraction, and dot product, as well as finding unit vectors.
Transcribed Image Text:**Vectors Problem Explanation** --- **Given:** - \( u = 1i - 3j \) - \( v = 2i + 3j \) **Tasks:** a) Calculate \( 2(u) - 3(v) \) \[ 2(1i - 3j) - 3(2i + 3j) \] \[ = (2i - 6j) - (6i + 9j) \] \[ = 2i - 6j - 6i - 9j \] \[ = -4i - 15j \] b) Calculate \( (i - 3j) \cdot (2i + 3j) \) - This involves finding the dot product: The dot product is calculated as: \[ (1 \cdot 2) + (-3 \cdot 3) = 2 - 9 = -7 \] c) Find a unit vector in the same direction as \( v \) - To find a unit vector, divide each component of \( v \) by its magnitude. - First, calculate the magnitude of \( v \): \[ \|v\| = \sqrt{2^2 + 3^2} = \sqrt{4 + 9} = \sqrt{13} \] - The unit vector in the direction of \( v \) is: \[ \frac{1}{\sqrt{13}}(2i + 3j) = \left(\frac{2}{\sqrt{13}}i + \frac{3}{\sqrt{13}}j\right) \] --- This set of problems helps understand vector arithmetic and operations such as scaling, subtraction, and dot product, as well as finding unit vectors.
Expert Solution
trending now

Trending now

This is a popular solution!

steps

Step by step

Solved in 2 steps with 2 images

Blurred answer
Recommended textbooks for you
Trigonometry (11th Edition)
Trigonometry (11th Edition)
Trigonometry
ISBN:
9780134217437
Author:
Margaret L. Lial, John Hornsby, David I. Schneider, Callie Daniels
Publisher:
PEARSON
Trigonometry (MindTap Course List)
Trigonometry (MindTap Course List)
Trigonometry
ISBN:
9781305652224
Author:
Charles P. McKeague, Mark D. Turner
Publisher:
Cengage Learning
Algebra and Trigonometry
Algebra and Trigonometry
Trigonometry
ISBN:
9781938168376
Author:
Jay Abramson
Publisher:
OpenStax
Trigonometry (MindTap Course List)
Trigonometry (MindTap Course List)
Trigonometry
ISBN:
9781337278461
Author:
Ron Larson
Publisher:
Cengage Learning