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Mathematics
Mathematics
Problem
Let
a
=
1111
…
1
a = 1111 \dots 1
a
=
1111
…
1
(55 digits),
b
=
1
+
10
+
10
2
+
⋯
+
10
4
b = 1 + 10 + 10^2 + \dots + 10^4
b
=
1
+
10
+
1
0
2
+
⋯
+
1
0
4
,
c
=
1
+
10
5
+
10
10
+
10
15
+
⋯
+
10
50
c = 1 + 10^5 + 10^{10} + 10^{15} + \dots + 10^{50}
c
=
1
+
1
0
5
+
1
0
10
+
1
0
15
+
⋯
+
1
0
50
, then (a)
a
=
b
+
c
a = b + c
a
=
b
+
c
(b)
a
=
b
c
a = bc
a
=
b
c
(c)
b
=
a
c
b = ac
b
=
a
c
(d)
c
=
a
b
c = ab
c
=
ab
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