Binomial Expansion(3)
2010-02-04 3:23 am
Given that x+1/x = 1, without directly solving x, find the value of x^7 + 1/x^7
回答 (2)
2010-02-04 4:24 am
2010-02-04 3:33 am
Given that x+1/x = 1, without directly
solving x, find the value of x^7 + 1/x^7
Sol
x+1/x=1
x+1/x=2(1/2)
x+1/x=2cos60度
x^7+1/x^7=2cos420度
x^7+1/x^7=2cos360度
x^7+1/x^7=1
收錄日期: 2021-04-22 00:45:50
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20100203000051KK01329