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©2025 数学クラブ http://sugaku.club/
月 日（ ）
● 有理化しなさい
[1P0-00]
(1)
1
19
(2)
1
13
(3)
1
5
(4)
1
5
(5)
1
2
(6)
1
17
(7)
1
2
(8)
1
2
(9)
1
13
(10)
1
19
(11)
1
7
(12)
1
5
(13)
1
13
(14)
1
2
©2025 数学クラブ http://sugaku.club/
月 日（ ）
【解答例】
(1)
1
19
19
1
×
19
=
=
19
19
×
19
(2)
1
13
13
1
×
13
=
=
13
13
×
13
(3)
1
5
5
1
×
5
=
=
5
5
×
5
(4)
1
5
5
1
×
5
=
=
5
5
×
5
(5)
1
2
2
1
×
2
=
=
2
2
×
2
(6)
1
17
17
1
×
17
=
=
17
17
×
17
(7)
1
2
2
1
×
2
=
=
2
2
×
2
(8)
1
2
2
1
×
2
=
=
2
2
×
2
(9)
1
13
13
1
×
13
=
=
13
13
×
13
(10)
1
19
19
1
×
19
=
=
19
19
×
19
(11)
1
7
7
1
×
7
=
=
7
7
×
7
(12)
1
5
5
1
×
5
=
=
5
5
×
5
(13)
1
13
13
1
×
13
=
=
13
13
×
13
(14)
1
2
2
1
×
2
=
=
2
2
×
2