Answer the question in a detailed manner.
1. 4k^(3/2) - 6k = 54
A question
2009-05-03 8:27 am
回答 (2)
2009-05-03 10:54 am
✔ 最佳答案
Let x = k1/24k3/2 - 6k = 54
4x3 - 6x2 = 54
2x3 - 3x2 - 27 = 0
(x - 3)(2x2 + 3x + 9) = 0
x = 3
k1/2 = 3
k = 9
2009-05-03 9:07 am
Let x=k^(1/2)
4k^(3/2) - 6k = 54
4x^3 - 6x = 54
x(2x-3)=27
=>2x^2-3x-27=0
(2x-9)(x+3)=0
x=9/2 or -3
So k=81/4
4k^(3/2) - 6k = 54
4x^3 - 6x = 54
x(2x-3)=27
=>2x^2-3x-27=0
(2x-9)(x+3)=0
x=9/2 or -3
So k=81/4
收錄日期: 2021-04-26 13:50:03
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20090503000051KK00054