Math Problem Statement

For the vector a = [6, 3, 1], find: 1. The length of a 2. The unit vector in the same direction as a

Solution

To solve this problem, let’s go through it step-by-step.

1. Finding the Length of Vector a

The vector a is given as: a=[631]\mathbf{a} = \begin{bmatrix} 6 \\ 3 \\ 1 \end{bmatrix} The length (or magnitude) of a vector a with components axa_x, aya_y, and aza_z is calculated using the formula: a=ax2+ay2+az2\|\mathbf{a}\| = \sqrt{a_x^2 + a_y^2 + a_z^2} For this vector: a=62+32+12=36+9+1=46\|\mathbf{a}\| = \sqrt{6^2 + 3^2 + 1^2} = \sqrt{36 + 9 + 1} = \sqrt{46} Thus, the length of a is: a=466.78\|\mathbf{a}\| = \sqrt{46} \approx 6.78

2. Finding the Unit Vector in the Same Direction as a

The unit vector in the direction of a is obtained by dividing each component of a by the magnitude a\|\mathbf{a}\|. The unit vector u in the direction of a is given by: u=1aa=146[631]\mathbf{u} = \frac{1}{\|\mathbf{a}\|} \mathbf{a} = \frac{1}{\sqrt{46}} \begin{bmatrix} 6 \\ 3 \\ 1 \end{bmatrix} Breaking this down, each component of the unit vector is: ux=646,uy=346,uz=146u_x = \frac{6}{\sqrt{46}}, \quad u_y = \frac{3}{\sqrt{46}}, \quad u_z = \frac{1}{\sqrt{46}} If we approximate these values: ux0.884,uy0.442,uz0.147u_x \approx 0.884, \quad u_y \approx 0.442, \quad u_z \approx 0.147 Thus, the unit vector u is: u[0.8840.4420.147]\mathbf{u} \approx \begin{bmatrix} 0.884 \\ 0.442 \\ 0.147 \end{bmatrix}

Summary of Answers

  • Length of a\mathbf{a}: 466.78\sqrt{46} \approx 6.78
  • Unit Vector in the Direction of a\mathbf{a}: [0.8840.4420.147]\begin{bmatrix} 0.884 \\ 0.442 \\ 0.147 \end{bmatrix}

Would you like more detailed steps, or do you have any questions about the solution?


Related Questions

  1. How do you find the magnitude of a 2-dimensional vector?
  2. What is the purpose of finding a unit vector?
  3. Can a unit vector have a negative component?
  4. How is vector addition performed?
  5. What are the applications of vectors in physics?

Tip

Always double-check your square root calculations, as rounding errors can impact the precision of your answers, especially when finding unit vectors.

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Vector Calculus
Vector Magnitude
Unit Vectors

Formulas

Magnitude of vector formula: |a| = √(x^2 + y^2 + z^2)
Unit vector formula: u = (1/|a|) * a

Theorems

-

Suitable Grade Level

Grades 10-12