✔ 最佳答案
a + b = 100 ...... (1)
ab = 200 ...... (2)
(1):
a = 100 - b ...... (3)
(3) 代入 (2):
(100 - b)b = 200
100b - b² = 200
b² - 100b + 200 = 0
b = [100 ± √(100² - 4 x 1 x 200)]/2
b = 50 + 10√23 或 b = 50 - 10√23
當 b = 50 + 10√23
(3):
a = 100 - (50 + 10√23)
a = 50 - 10√23
當 b = 50 - 10√23
(3):
a = 100 - (50 - 10√23)
a = 50 + 10√23
答:
a = 50 + 10√23 及 b = 50 - √23
或 a = 50 - 10√23 及 b = 50 + √23
2010-04-22 22:43:45 補充:
答案打漏字,應為:
答:
a = 50 + 10√23 及 b = 50 - 10√23
或 a = 50 - 10√23 及 b = 50 + 10√23