推 highperpopo : 感謝解答 03/20 15:59
※ 引述《highperpopo (大頭)》之銘言:
: http://i.imgur.com/oIhZCp8.jpg
: 請問一下這題不知道如何算
|ax + 2| > b
=> x > 7 或 x < 1
|a||x + 2/a| > b
=> |x - (-2/a)| > b/|a|
-2/a = [7 + 1]/2
= 4
=> a = -1/2
b/|a| = 3
=> b = 3/2
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