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Mathematics
Problem
For any vector
a
\mathbf{a}
a
, the value of
(
a
×
i
^
)
2
+
(
a
×
j
^
)
2
+
(
a
×
k
^
)
2
(\mathbf{a} \times \hat{i})^2 + (\mathbf{a} \times \hat{j})^2 + (\mathbf{a} \times \hat{k})^2
(
a
×
i
^
)
2
+
(
a
×
j
^
)
2
+
(
a
×
k
^
)
2
is equal to a.
4
a
2
4\mathbf{a}^2
4
a
2
b.
2
a
2
2\mathbf{a}^2
2
a
2
c.
a
2
\mathbf{a}^2
a
2
d.
3
a
2
3\mathbf{a}^2
3
a
2
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