The value of the following expression `hati.(hatjxxhatk)+j.(hatixxhatk)+hatk.(hatjxxhati)`is
a) 0
b) 1
c) -1
d) 3
A
0
B
1
C
`-1`
D
3
Text Solution
AI Generated Solution
The correct Answer is:
To solve the expression \( \hat{i} \cdot (\hat{j} \times \hat{k}) + \hat{j} \cdot (\hat{i} \times \hat{k}) + \hat{k} \cdot (\hat{j} \times \hat{i}) \), we will follow these steps:
### Step 1: Calculate \( \hat{j} \times \hat{k} \)
Using the right-hand rule for cross products:
\[
\hat{j} \times \hat{k} = \hat{i}
\]
### Step 2: Calculate \( \hat{i} \cdot (\hat{j} \times \hat{k}) \)
Now substituting the result from Step 1:
\[
\hat{i} \cdot \hat{i} = 1
\]
### Step 3: Calculate \( \hat{i} \times \hat{k} \)
Using the right-hand rule for cross products:
\[
\hat{i} \times \hat{k} = -\hat{j}
\]
### Step 4: Calculate \( \hat{j} \cdot (\hat{i} \times \hat{k}) \)
Now substituting the result from Step 3:
\[
\hat{j} \cdot (-\hat{j}) = -1
\]
### Step 5: Calculate \( \hat{j} \times \hat{i} \)
Using the right-hand rule for cross products:
\[
\hat{j} \times \hat{i} = -\hat{k}
\]
### Step 6: Calculate \( \hat{k} \cdot (\hat{j} \times \hat{i}) \)
Now substituting the result from Step 5:
\[
\hat{k} \cdot (-\hat{k}) = -1
\]
### Step 7: Combine all the results
Now we combine all the results from Steps 2, 4, and 6:
\[
1 + (-1) + (-1) = 1 - 1 - 1 = -1
\]
### Final Answer
Thus, the value of the expression is:
\[
\boxed{-1}
\]
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