算24点，要求写出算式：1，2，5，7还有2，3，5，5，运用乘方，加减乘除运算

(1×(2×(5+7)))

((1×2)×(5+7))

(1×(2×(7+5)))

((1×2)×(7+5))

((5-2)×(5+3))

((5-(2-5))×3)

(((5-2)+5)×3)

((5-2)×(3+5))

(5+5-2)*3

（1＋7）＊（5－2）＝24，（5＋5－2）＊3＝24

1: 1 × (2 × (5 + 7))
2: 1 × 2 ×(5 + 7)
3: (1 × 2) × (5 + 7)
4: 1 × (2 × (7 + 5))
5: 1 × 2 ×(7 + 5)
6: (1 × 2) × (7 + 5)
7: (1 × 5 + 7) × 2
8: ((1 × 5) + 7) × 2
9: (1 × (5 + 7)) × 2
10: 1 × (5 + 7) × 2
11: 1 × ((5 + 7) × 2)
12: (1 + 7) × (5 - 2)
13: (1 × 7 + 5) × 2
14: ((1 × 7) + 5) × 2
15: (1 × (7 + 5)) × 2
16: 1 × (7 + 5) × 2
17: 1 × ((7 + 5) × 2)
18: 2 × (1 × 5 + 7)
19: 2 × ((1 × 5) + 7)
20: 2 × (1 × (5 + 7))
21: 2 × 1 ×(5 + 7)
22: (2 × 1) × (5 + 7)
23: 2 ÷ 1 ×(5 + 7)
24: (2 ÷ 1) × (5 + 7)
25: 2 ÷ (1 ÷ (5 + 7))
26: 2 × (1 × 7 + 5)
27: 2 × ((1 × 7) + 5)
28: 2 × (1 × (7 + 5))
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