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Mathematics
Mathematics
Problem
Let
A
=
[
a
i
j
]
2
×
2
A = [a_{ij}]_{2 \times 2}
A
=
[
a
ij
]
2
×
2
, where
a
i
j
≠
0
a_{ij} \neq 0
a
ij
=
0
for all
i
,
j
i, j
i
,
j
and
A
2
=
I
A^2 = I
A
2
=
I
, Let
a
a
a
be the sum of all diagonal elements of
A
A
A
and
b
=
∣
A
∣
b = |A|
b
=
∣
A
∣
Then
3
a
2
+
4
b
2
3a^2 + 4b^2
3
a
2
+
4
b
2
is equal to
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