if x^1/2+x^ -1/2
x+x^ -1
show step,,,plz,,,,need it immediately
maths,,,10分PLZ
2007-10-06 7:12 am
回答 (2)
2007-10-06 7:44 am
✔ 最佳答案
x^1/2+x^ -1/2 = 3(x^1/2+x^ -1/2)^2 = 3^2.........take square both sides
(x^1/2)^2+2(x^1/2)(x^-1/2)+(x^-1/2)^2 = 9
x+2+x^-1 = 9
x+x^-1 = 9-2
x+x^-1 = 7
p.s. (x^1/2)^2 = x
(x^-1/2)^2 = x^-1
(x^1/2)(x^-1/2)
=(x^1/2)[1/(x^1/2)]
=1
2007-10-06 7:26 am
唔多明"
請問你個問題想問咩?
if x^1/2+x^ -1/2 = x+x^ -1 ←咁樣ar?
2007-10-05 23:53:53 補充：
恕我問多句..e 題數 form 幾架?
請問你個問題想問咩?
if x^1/2+x^ -1/2 = x+x^ -1 ←咁樣ar?
2007-10-05 23:53:53 補充：
恕我問多句..e 題數 form 幾架?
收錄日期: 2021-04-13 13:46:16
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