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Category: Integration

P-rove-that-dx-b-4-2ax-2-c-tan-1-2-a-x-c-b-4-2-a-c-b-4-C-if-a-c-b-4-gt-0-

Question Number 202388 by Calculusboy last updated on 25/Dec/23 $$\:\:\boldsymbol{{P}}\:\boldsymbol{{rove}}\:\boldsymbol{{that}}:\:\:\:\:\int\:\frac{\boldsymbol{{dx}}}{\boldsymbol{{b}}^{\mathrm{4}} +\mathrm{2}\boldsymbol{{ax}}^{\mathrm{2}} +\boldsymbol{{c}}}=\frac{\boldsymbol{{tan}}^{−\mathrm{1}} \left(\frac{\sqrt{\mathrm{2}}\sqrt{\boldsymbol{{a}}}\boldsymbol{{x}}}{\:\sqrt{\boldsymbol{{c}}+\boldsymbol{{b}}^{\mathrm{4}} }}\right)}{\:\sqrt{\mathrm{2}}\sqrt{\boldsymbol{{a}}}\sqrt{\boldsymbol{{c}}+\boldsymbol{{b}}^{\mathrm{4}} }}+\boldsymbol{{C}} \\ $$$$\boldsymbol{{if}}\:\:\boldsymbol{{a}}\centerdot\left(\boldsymbol{{c}}+\boldsymbol{{b}}^{\mathrm{4}} \right)>\mathrm{0} \\ $$$$ \\ $$ Answered by witcher3…

sin-3x-1-sin-3-x-dx-

Question Number 202125 by Calculusboy last updated on 21/Dec/23 $$\int\:\frac{\boldsymbol{{sin}}\left(\mathrm{3}\boldsymbol{{x}}\right)}{\mathrm{1}+\boldsymbol{{sin}}^{\mathrm{3}} \boldsymbol{{x}}}\boldsymbol{{dx}} \\ $$ Answered by Frix last updated on 21/Dec/23 $$\mathrm{Let}\:{s}=\mathrm{sin}\:{x} \\ $$$$\frac{\mathrm{sin}\:\mathrm{3}{x}}{\mathrm{1}+\mathrm{sin}^{\mathrm{3}} \:{x}}=\frac{{s}\left(\mathrm{4}{s}^{\mathrm{2}} −\mathrm{3}\right)}{\left({s}+\mathrm{1}\right)\left({s}^{\mathrm{2}}…

Question-202127

Question Number 202127 by Calculusboy last updated on 21/Dec/23 Answered by qaz last updated on 21/Dec/23 $$\int_{\pi/\mathrm{6}} ^{\pi/\mathrm{3}} \frac{{dx}}{\mathrm{1}+\mathrm{tan}^{\pi} \:{x}}=\int_{\pi/\mathrm{6}} ^{\pi/\mathrm{3}} \frac{{dx}}{\mathrm{1}+\mathrm{cot}\:^{\pi} {x}}=\frac{\mathrm{1}}{\mathrm{2}}\int_{\pi/\mathrm{6}} ^{\pi/\mathrm{3}} \left(\frac{\mathrm{1}}{\mathrm{1}+\mathrm{tan}^{\pi}…

Question-201817

Question Number 201817 by Calculusboy last updated on 13/Dec/23 Answered by witcher3 last updated on 13/Dec/23 $$=\int\left(\mathrm{sin}\left(\mathrm{ln}\left(\mathrm{x}+\mathrm{1}\right)\right)\left(\sqrt{\mathrm{x}+\mathrm{1}}−\mathrm{1}\right)\right)^{\mathrm{2}} \mathrm{dx} \\ $$$$=\int\mathrm{sin}^{\mathrm{2}} \left(\mathrm{ln}\left(\mathrm{x}+\mathrm{1}\right)\right)\left(\mathrm{x}+\mathrm{2}−\mathrm{2}\sqrt{\mathrm{x}+\mathrm{1}}\right) \\ $$$$\mathrm{ln}\left(\sqrt{\mathrm{x}+\mathrm{1}}\right)=\mathrm{t} \\ $$$$\mathrm{x}+\mathrm{1}=\mathrm{e}^{\mathrm{2t}}…