cos pi x

Fun with maths: prove Cos pi/7 + cos 3pi/7 + cos 5pi/7=1/2被捕魚的假器具插入嘴巴,因而死亡的海獅。.....誤入廢棄塑膠圈的海獅頸被割傷。.....被捕魚器具插入嘴巴的海獅。.....被漁具纏住因而溺死的海獅。...... 人類隨手亂丟的垃圾以及捕魚工具,現在竟成了危害海洋動物生命的罪魁禍首!阿拉斯加漁獵部(Alaska Department of FisTo prove Cos pi/7 + cos 3pi/7 + cos 5pi/7=1/2 let z = cos pi/7 + i sin pi/7 z^7 = cos pi + i sin pi = - 1 so z^7+1 = 0 (z+1) (z^6-z^5+z^4 - z^3+z^2 -z + 1) = 0 as z is not - 1 so z^6-z^5+z^4 - z^3+z^2 -z + 1 = 0 so z^6-z^5+z^4 - z^3+z^2 -z= -1 so z+z^3+ z...

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(p.455 Ex22) Integral de 0 a pi/2 de sen^2(2x).cos^3(2x) - YouTube看到大卡車~還是閃遠點吧!!! 6.1 Valor Medio y Valor RMS de una señal senoidal - Duration: 14:59. by Fernando Ramirez 17,718 views 14:59 Play next Play now Integral de x^5.e^(x^2) - Duration: 5:06. by Luís Cláudio LA 5,986 views 5:06 Play next Play now Integral definida con ......

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