if a <3 , c<2a , prove 5a+6c < 51
if i solve this question like this ,is there any problem ?
c<2a
6c<12a
a<3
12a<36
6c<12a<36
6c<36...............(1)
a<3
5a<15.........(2)
6c<36
6c+5a<36+15...........(1)+(2)
6C+5a <51
F3 MATHS inequality
2007-01-07 6:15 pm
回答 (2)
2007-01-07 6:23 pm
✔ 最佳答案
Your answer is correct, but it can be simplified like this:5a + 6c
< 5a + 6(2a) , since given c < 2a
= 17a
< 17(3) , since given a < 3
= 51.
收錄日期: 2021-04-12 23:19:33
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20070107000051KK00992