大一数学题求解答

最好能手写拍给我,麻烦把详细步骤给我真的急需
2025-05-12 03:00:26
推荐回答(1个)
回答1:

因为

(a+b)/ab = 3
(b+c)/bc = 4
(a+c)/ac = 5
即:
1/a + 1/b = 3
1/b + 1/c = 4
1/a + 1/c = 5
三式相加,得:
2(1/a + 1/b + 1/c) = 12
所以:1/a + 1/b + 1/c = 6

1/a + 1/b + 1/c
=(ab+bc+ca)/abc
=(ab+bc+ca)/abc
= 6

所以

取倒数:abc/(ab+bc+ca) = 1/6

希望对你有帮助 谢谢