Menu Close

Category: Integration

Question-100956

Question Number 100956 by bobhans last updated on 29/Jun/20 Answered by john santu last updated on 29/Jun/20 $$\mathrm{set}\:\mathrm{ln}\left(\mathrm{x}\right)\:=\:\mathrm{z}\:\rightarrow\begin{cases}{\mathrm{z}=\mathrm{1}}\\{\mathrm{z}=\mathrm{e}}\end{cases} \\ $$$$\left.\mathrm{I}=\:\underset{\mathrm{1}} {\overset{\mathrm{e}} {\int}}\:\mathrm{ln}\left(\mathrm{z}\right).\:\mathrm{z}\:\mathrm{dz}\:=\:\frac{\mathrm{1}}{\mathrm{2}}\mathrm{z}^{\mathrm{2}} .\mathrm{ln}\left(\mathrm{z}\right)\right]_{\mathrm{1}} ^{\mathrm{e}} −\frac{\mathrm{1}}{\mathrm{2}}\overset{\mathrm{e}}…

Question-166491

Question Number 166491 by mathlove last updated on 21/Feb/22 Commented by cortano1 last updated on 21/Feb/22 $$\:\:=\:\frac{\mathrm{1}}{\mathrm{16}}\mathrm{x}−\frac{\mathrm{1}}{\mathrm{64}}\:\mathrm{sin}\:\mathrm{4x}\:+\frac{\mathrm{1}}{\mathrm{48}}\:\mathrm{sin}\:^{\mathrm{3}} \mathrm{2x}\:+\:\mathrm{c} \\ $$ Commented by mathlove last updated…

B-sin-2x-1-cos-2x-1-dx-

Question Number 166488 by bobhans last updated on 21/Feb/22 $$\:\:\:\mathrm{B}=\int\:\sqrt{\frac{\mathrm{sin}\:\mathrm{2x}−\mathrm{1}}{\mathrm{cos}\:\mathrm{2x}−\mathrm{1}}}\:\mathrm{dx}\:=? \\ $$ Answered by greogoury55 last updated on 21/Feb/22 $$\:\:\:{B}=\int\:\sqrt{\frac{\mathrm{1}−\mathrm{sin}\:\mathrm{2}{x}}{\mathrm{1}−\mathrm{cos}\:\mathrm{2}{x}}}\:{dx} \\ $$$$\:\:\:{B}=\int\:\sqrt{\frac{\mathrm{sin}\:^{\mathrm{2}} {x}+\mathrm{cos}\:^{\mathrm{2}} {x}−\mathrm{2sin}\:{x}\:\mathrm{cos}\:{x}}{\mathrm{2sin}\:^{\mathrm{2}} {x}}}\:{dx}…

Question-100948

Question Number 100948 by Dwaipayan Shikari last updated on 29/Jun/20 Commented by Dwaipayan Shikari last updated on 29/Jun/20 $$\:\:\:\:\:\underset{{n}\rightarrow\infty} {\mathrm{lim}}\:\frac{\mathrm{1}}{{n}}\:\underset{{r}=\mathrm{1}} {\overset{{n}} {\sum}}\left(\frac{{r}}{{n}}\right){sec}^{\mathrm{2}} \left(\frac{{r}}{{n}}\right)^{\mathrm{2}} \\ $$$$\:\:\:\:\:\:\:\:\:\:\:\int_{\mathrm{0}}…

Show-that-n-1-1-n-H-n-n-2-5-8-3-m-n-

Question Number 166436 by mnjuly1970 last updated on 20/Feb/22 $$ \\ $$$$\:\:\:\:\:\:\mathrm{S}{how}\:{that}\:: \\ $$$$ \\ $$$$\:\:\:\:\:\:\:\:\underset{{n}=\mathrm{1}} {\overset{\infty} {\sum}}\:\frac{\left(−\mathrm{1}\right)^{\:{n}} \:{H}_{\:{n}} }{{n}^{\:\mathrm{2}} }\:\:=\:−\frac{\mathrm{5}}{\mathrm{8}}\:\zeta\:\left(\mathrm{3}\:\right)\:\:\:\:\:\:\:\:\:\:\:\blacksquare\:{m}.{n}\:\:\:\:\:\:\:\:\:\:\:\:\: \\ $$$$\:\:\:\:\:−−−−−−−−− \\ $$…