解下列各方程,答案以弧度表示。
3(3^(sinx) +3^(-sinx))=10
a-maths~~~~~~
2007-10-13 9:33 pm
回答 (1)
2007-10-13 10:08 pm
✔ 最佳答案
3(3^(sinx) +3^(-sinx))=10 3．3^(sinx) + 3．3^(-sinx)=10
3．3^(2sinx) + 3 = 10．3^(sinx)
3．(3^(sinx))^2 - 10．3^(sinx) + 3 = 0
(3．3^(sinx) - 1)(3^(sinx) - 3) = 0
3^(sinx) = 1/3 or 3
3^(sinx) = 3^(-1) or 3^1
sinx = -1 or 1
x = 3pi/2 or pi/2
收錄日期: 2021-04-13 18:12:46
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20071013000051KK02010