设S(x)=∫0x|cost|dt. (1)证明:当nπ≤x<(n+1)x时,2n≤S(x)<2(η+1); (2)求

admin2021-12-14  6

问题 设S(x)=∫0x|cost|dt.
(1)证明:当nπ≤x<(n+1)x时,2n≤S(x)<2(η+1);
(2)求

选项

答案(1)当nπ≤x<(n+1)π时,∫0|cost|dt≤∫0x|cost|dt<∫0(n+1)π|cost|dt, ∫0|cost|dt=n∫0π|cost|dt=[*] ∫0(n+1)π|cost|dt=2(n+1),则2n≤S(x)<2(n+1). (2)由nπ≤x<(n+1)π,得1/[(n+1)π]<1/x≤1/nπ, [*]

解析
转载请注明原文地址:https://www.kaotiyun.com/show/Yjl4777K
0

最新回复(0)