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(C) Given that $\hat{i}, \hat{j}, \hat{k}$ are unit vectors along the positive $x, y, z$-axes respectively.$(a)$ $\sum \hat{i} 	imes(\hat{j}+\hat{k})

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$\sum \hat{i} \cdot(\hat{j} 	imes \hat{k})=\vec{0}$

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(C) Given that $\hat{i}, \hat{j}, \hat{k}$ are unit vectors along the positive $x, y, z$-axes respectively.$(a)$ $\sum \hat{i} 	imes(\hat{j}+\hat{k}) = \hat{i} 	imes(\hat{j}+\hat{k}) + \hat{j} 	imes(\hat{k}+\hat{i}) + \hat{k} 	imes(\hat{i}+\hat{j})$$= (\hat{k} - \hat{j}) + (\hat{i} - \hat{k}) + (\hat{j} - \hat{i}) = \vec{0}$. This is true.$(b)$ $\sum \hat{i} 	imes(\hat{j} 	imes \hat{k}) = \hat{i} 	imes \hat{i} + \hat{j} 	imes \hat{j} + \hat{k} 	imes \hat{k} = \vec{0} + \vec{0} + \vec{0} = \vec{0}$. This is true.$(c)$ $\sum \hat{i} \cdot(\hat{j} 	imes \hat{k}) = \hat{i} \cdot \hat{i} + \hat{j} \cdot \hat{j} + \hat{k} \cdot \hat{k} = 1 + 1 + 1 = 3$. This is false as it is not equal to $\vec{0}$.$(d)$ $\sum \hat{i} \cdot(\hat{j}+\hat{k}) = (\hat{i} \cdot \hat{j} + \hat{i} \cdot \hat{k}) + (\hat{j} \cdot \hat{k} + \hat{j} \cdot \hat{i}) + (\hat{k} \cdot \hat{i} + \hat{k} \cdot \hat{j}) = 0 + 0 + 0 = 0$. This is true.

If $\hat{i}, \hat{j}, \hat{k}$ are unit vectors along the positive direction of $x, y$ and $z$-axes,then which of the following is a false statement?

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