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Category: Integration

calculate-0-2pi-cos-2x-2cosx-sin-x-dx-

Question Number 62732 by mathmax by abdo last updated on 24/Jun/19 calculate02πcos(2x)2cosxsin(x)dx Answered by MJS last updated on 24/Jun/19 $$\frac{\mathrm{cos}\:\left(\mathrm{2}\left({x}+\pi\right)\right)}{\mathrm{2cos}\:\left({x}+\pi\right)\:−\mathrm{sin}\:\left({x}+\pi\right)}=−\frac{\mathrm{cos}\:\mathrm{2}{x}}{\mathrm{2cos}\:{x}\:−\mathrm{sin}\:{x}}\:\Rightarrow \

Question-128251

Question Number 128251 by rs4089 last updated on 05/Jan/21 Answered by mathmax by abdo last updated on 05/Jan/21 $$\mathrm{let}\:\mathrm{I}\:=\int_{−\infty} ^{+\infty} \:\mathrm{x}^{\mathrm{2}} \:\mathrm{e}^{−\mathrm{x}^{\mathrm{2}} \:} \mathrm{cosx}\:\mathrm{dx}\:\Rightarrow\mathrm{I}\:=\int_{−\infty} ^{+\infty}…

nice-calculus-prove-that-0-pi-4-ln-sin-x-d-pi-4-log-2-G-2-log-2sin-x-n-1-1-n-cos-2nx-0-pi-4-log-2-n-1-cos-2nx-n

Question Number 128244 by mnjuly1970 last updated on 05/Jan/21 nicecalculusprovethat::Ω=0π4ln(sin(x))d=π4log(2)G2log(2sin(x))=n=11ncos(2nx)$$\:\Omega=\:\int_{\mathrm{0}} ^{\:\frac{\pi}{\mathrm{4}}} \left\{−{log}\left(\mathrm{2}\right)−\underset{{n}=\mathrm{1}} {\overset{\infty} {\sum}}\frac{{cos}\left(\mathrm{2}{nx}\right)}{{n}}\right\}{dx} \