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Mathematics
Mathematics
Problem
Let
A
=
[
1
0
x
1
]
A=\begin{bmatrix}1&0\\x&1\end{bmatrix}
A
=
[
1
x
0
1
]
and
B
=
[
1
2
0
1
]
B=\begin{bmatrix}1&2\\0&1\end{bmatrix}
B
=
[
1
0
2
1
]
, where
x
∈
R
x\in\mathbb R
x
∈
R
. For which value of
x
x
x
does
A
B
=
B
A
AB = BA
A
B
=
B
A
? a)
1
1
1
b)
0
0
0
c)
−
1
2
-\dfrac12
−
2
1
d)
−
1
-1
−
1
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