Expand : (t - 1/t)(t + 1/t)?
回答 (3)
2010-02-03 12:10 pm
✔ 最佳答案
t^2-1/t^2 answer//
2010-02-03 2:01 pm
(t - 1/t)(t + 1/t)
= t(t) + t(1/t) - 1/t(t) - 1/t(1/t)
= t^2 + 1 - 1 - 1/(t^2)
= t^2 - 1/(t^2)
= t(t) + t(1/t) - 1/t(t) - 1/t(1/t)
= t^2 + 1 - 1 - 1/(t^2)
= t^2 - 1/(t^2)
2010-02-03 12:22 pm
Assuming that question reads as :-
[ t - (1/t ) ] [ t + (1/t) ]
t ² + 1 - 1 - 1/ t ²
t ² - 1/t ²
[ t - (1/t ) ] [ t + (1/t) ]
t ² + 1 - 1 - 1/ t ²
t ² - 1/t ²
收錄日期: 2021-05-01 13:01:00
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20100203034916AAmA3Jz