knowing-that-cos-x-n-1-1-n-x-2n-2n-sin-x-n-1-1-n-x-2n-1-2n-1-prof-that-cos-x-y-cos-x-cos-y-sin-x-sin-y-

Question Number 58358 by Mahmoud A.R last updated on 22/Apr/19

knowing that: cos(x)=Σ_(n=1) ^∞ (((−1)^n x^(2n) )/((2n)!)) sin(x)=Σ_(n=1) ^∞ (((−1)^n x^(2n+1) )/((2n +1)!)) prof that: cos(x+y)= cos(x)cos(y)−sin(x)sin(y)

$${knowing}\:{that}:\: \\ $$$${cos}\left({x}\right)=\underset{{n}=\mathrm{1}} {\overset{\infty} {\sum}}\frac{\left(−\mathrm{1}\right)^{{n}} {x}^{\mathrm{2}{n}} }{\left(\mathrm{2}{n}\right)!}\:\:\:\: \\ $$$${sin}\left({x}\right)=\underset{{n}=\mathrm{1}} {\overset{\infty} {\sum}}\frac{\left(−\mathrm{1}\right)^{{n}} {x}^{\mathrm{2}{n}+\mathrm{1}} }{\left(\mathrm{2}{n}\:+\mathrm{1}\right)!} \\ $$$${prof}\:{that}:\:{cos}\left({x}+{y}\right)=\:{cos}\left({x}\right){cos}\left({y}\right)−{sin}\left({x}\right){sin}\left({y}\right) \\ $$

Facebook Tweet Pin

knowing-that-cos-x-n-1-1-n-x-2n-2n-sin-x-n-1-1-n-x-2n-1-2n-1-prof-that-cos-x-y-cos-x-cos-y-sin-x-sin-y-

Leave a Reply Cancel reply