-2x²+x+2小過等於0
用配方法點計?!
-2x²+x+2小過等於0
2011-06-06 3:03 am
回答 (2)
2011-06-06 4:13 am
2011-06-06 4:52 am
-2x²+x+2=-(x-2)(x+1) <=0
=> (x-2)(x+1)>=0
x<=-1 or x >=2
=> (x-2)(x+1)>=0
x<=-1 or x >=2
收錄日期: 2021-04-23 22:04:44
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20110605000051KK00766