1.f(x)=a sin(πx+α)+b con(πx+β),其中a,b,α,β都是不为0的实数,且满足f(2000)=-1,求:f(2002)D的值2.f(x)=sin(πx/3),求f(1)+f(2)+f(3)+.+f(2004)的值.第2问中,最小正周期等于6是怎么算的?
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![1.f(x)=a sin(πx+α)+b con(πx+β),其中a,b,α,β都是不为0的实数,且满足f(2000)=-1,求:f(2002)D的值2.f(x)=sin(πx/3),求f(1)+f(2)+f(3)+.+f(2004)的值.第2问中,最小正周期等于6是怎么算的?](/uploads/image/z/4451305-49-5.jpg?t=1.f%28x%29%3Da+sin%28%CF%80x%2B%CE%B1%29%2Bb+con%28%CF%80x%2B%CE%B2%29%2C%E5%85%B6%E4%B8%ADa%2Cb%2C%CE%B1%2C%CE%B2%E9%83%BD%E6%98%AF%E4%B8%8D%E4%B8%BA0%E7%9A%84%E5%AE%9E%E6%95%B0%2C%E4%B8%94%E6%BB%A1%E8%B6%B3f%282000%29%3D-1%2C%E6%B1%82%3Af%282002%29D%E7%9A%84%E5%80%BC2.f%28x%29%3Dsin%28%CF%80x%2F3%29%2C%E6%B1%82f%281%29%2Bf%282%29%2Bf%283%29%2B.%2Bf%282004%29%E7%9A%84%E5%80%BC.%E7%AC%AC2%E9%97%AE%E4%B8%AD%EF%BC%8C%E6%9C%80%E5%B0%8F%E6%AD%A3%E5%91%A8%E6%9C%9F%E7%AD%89%E4%BA%8E6%E6%98%AF%E6%80%8E%E4%B9%88%E7%AE%97%E7%9A%84%EF%BC%9F)
1.f(x)=a sin(πx+α)+b con(πx+β),其中a,b,α,β都是不为0的实数,且满足f(2000)=-1,求:f(2002)D的值2.f(x)=sin(πx/3),求f(1)+f(2)+f(3)+.+f(2004)的值.第2问中,最小正周期等于6是怎么算的?
1.f(x)=a sin(πx+α)+b con(πx+β),其中a,b,α,β都是不为0的实数,且满足f(2000)=-1,求:f(2002)D的值
2.f(x)=sin(πx/3),求f(1)+f(2)+f(3)+.+f(2004)的值.
第2问中,最小正周期等于6是怎么算的?
1.f(x)=a sin(πx+α)+b con(πx+β),其中a,b,α,β都是不为0的实数,且满足f(2000)=-1,求:f(2002)D的值2.f(x)=sin(πx/3),求f(1)+f(2)+f(3)+.+f(2004)的值.第2问中,最小正周期等于6是怎么算的?
1.f(2000)=a sin(2000π+α)+b con(2000π+β)=asinα+bcosβ=-1
同理f(2002)=-1
(思路:别忘了y=sinx y=cosx的最小正周期是2π)
2.原式=sin(π/3)+sin(2π/3)+sin(3π/3)+...+sin(2004π/3)
∵T=6 ∴原式=334[sin(π/3)+sin(2π/3)+sin(3π/3)+sin(4π/3)+sin(5π/3)+sin(6π/3)]=334*(根号3/2+根号3/2+0-根号3/2-根号3/2+0)=0(思路:还是用到周期,最小正周期是6,从1-2004刚好是6的334倍,因此算前6个再乘以334就OK)
自己问老师