Discover the answers to your questions at Westonci.ca, where experts share their knowledge and insights with you. Explore a wealth of knowledge from professionals across various disciplines on our comprehensive Q&A platform. Our platform offers a seamless experience for finding reliable answers from a network of knowledgeable professionals.

Determine the scalar product of [tex][tex]$A = 6i + 4j - 2k$[/tex][/tex] and [tex][tex]$B = 5i - 6j - 3k$[/tex][/tex].

A. [tex][tex]$30i + 24j + 6k$[/tex][/tex]
B. [tex][tex]$30i - 24j + 6k$[/tex][/tex]
C. 12
D. 60

Sagot :

Answer:To determine the scalar product (dot product) of the vectors \(\mathbf{A} = 6\mathbf{i} + 4\mathbf{j} - 2\mathbf{k}\) and \(\mathbf{B} = 5\mathbf{i} - 6\mathbf{j} - 3\mathbf{k}\), we use the formula for the dot product of two vectors \(\mathbf{A}\) and \(\mathbf{B}\):

\[

\mathbf{A} \cdot \mathbf{B} = A_x B_x + A_y B_y + A_z B_z

\]

Where \(\mathbf{A} = A_x \mathbf{i} + A_y \mathbf{j} + A_z \mathbf{k}\) and \(\mathbf{B} = B_x \mathbf{i} + B_y \mathbf{j} + B_z \mathbf{k}\).

Given:

\[

\mathbf{A} = 6\mathbf{i} + 4\mathbf{j} - 2\mathbf{k}

\]

\[

\mathbf{B} = 5\mathbf{i} - 6\mathbf{j} - 3\mathbf{k}

\]

The components are:

\[

A_x = 6, \quad A_y = 4, \quad A_z = -2

\]

\[

B_x = 5, \quad B_y = -6, \quad B_z = -3

\]

Now we calculate the dot product:

\[

\mathbf{A} \cdot \mathbf{B} = (6 \times 5) + (4 \times -6) + (-2 \times -3)

\]

Performing the multiplications:

\[

6 \times 5 = 30

\]

\[

4 \times -6 = -24

\]

\[

-2 \times -3 = 6

\]

Adding these results together:

\[

30 + (-24) + 6 = 30 - 24 + 6 = 12

\]

Thus, the scalar product of \(\mathbf{A}\) and \(\mathbf{B}\) is 12.

### Answer:

C. 12

Step-by-step explanation:Certainly! Let's go through the steps to find the scalar product (dot product) of vectors \( A = 6i + 4j - 2k \) and \( B = 5i - 6j - 3k \).

The formula for the scalar product (dot product) of two vectors \( A = (a_1, a_2, a_3) \) and \( B = (b_1, b_2, b_3) \) is given by:

\[

A \cdot B = a_1 \cdot b_1 + a_2 \cdot b_2 + a_3 \cdot b_3

\]

In our case, vector \( A \) is \( 6i + 4j - 2k \) and vector \( B \) is \( 5i - 6j - 3k \).

1. Identify the components of vector \( A \):

  - \( a_1 = 6 \)

  - \( a_2 = 4 \)

  - \( a_3 = -2 \)

2. Identify the components of vector \( B \):

  - \( b_1 = 5 \)

  - \( b_2 = -6 \)

  - \( b_3 = -3 \)

3. Apply the formula for the scalar product:

\[

A \cdot B = (6 \cdot 5) + (4 \cdot (-6)) + (-2 \cdot (-3))

\]

4. Calculate each term:

  - \( 6 \cdot 5 = 30 \)

  - \( 4 \cdot (-6) = -24 \)

  - \( -2 \cdot (-3) = 6 \)

5. Add these results together:

\[

A \cdot B = 30 + (-24) + 6

\]

6. Simplify the expression:

\[

A \cdot B = 30 - 24 + 6

\]

\[

A \cdot B = 12

\]

Therefore, the scalar product (dot product) of vectors \( A \) and \( B \) is \( \boxed{12} \). This confirms that option C, which states 12, is the correct answer.