Question and Answers Forum

All Questions      Topic List

Integration Questions

Previous in All Question      Next in All Question      

Previous in Integration      Next in Integration      

Question Number 182962 by universe last updated on 17/Dec/22

Answered by mr W last updated on 17/Dec/22

Commented by mr W last updated on 17/Dec/22

V=∫_0 ^2 xzdy    =∫_0 ^2 (4−y^2 )(2−y)dy    =∫_0 ^2 (8−2y^2 −4y+y^3 )dy    =[8y−((2y^3 )/3)−2y^2 +(y^4 /4)]_0 ^2     =8×2−((2×2^3 )/3)−2×2^2 +(2^4 /4)    =((20)/3)

$${V}=\int_{\mathrm{0}} ^{\mathrm{2}} {xzdy} \\ $$$$\:\:=\int_{\mathrm{0}} ^{\mathrm{2}} \left(\mathrm{4}−{y}^{\mathrm{2}} \right)\left(\mathrm{2}−{y}\right){dy} \\ $$$$\:\:=\int_{\mathrm{0}} ^{\mathrm{2}} \left(\mathrm{8}−\mathrm{2}{y}^{\mathrm{2}} −\mathrm{4}{y}+{y}^{\mathrm{3}} \right){dy} \\ $$$$\:\:=\left[\mathrm{8}{y}−\frac{\mathrm{2}{y}^{\mathrm{3}} }{\mathrm{3}}−\mathrm{2}{y}^{\mathrm{2}} +\frac{{y}^{\mathrm{4}} }{\mathrm{4}}\right]_{\mathrm{0}} ^{\mathrm{2}} \\ $$$$\:\:=\mathrm{8}×\mathrm{2}−\frac{\mathrm{2}×\mathrm{2}^{\mathrm{3}} }{\mathrm{3}}−\mathrm{2}×\mathrm{2}^{\mathrm{2}} +\frac{\mathrm{2}^{\mathrm{4}} }{\mathrm{4}} \\ $$$$\:\:=\frac{\mathrm{20}}{\mathrm{3}} \\ $$

Commented by universe last updated on 18/Dec/22

thanks sir

$${thanks}\:{sir} \\ $$

Answered by manxsol last updated on 18/Dec/22

D={(x,y,z)/0≪x≪4;  0≪y≪(√(4−x))  ;  0≪z≪2−y  x is variable free  ∫_0 ^( 4) ∫_0 ^(√(4−x)) ∫_(.0) ^(2−y) dzdydx  ∫_0 ^(√(4−x)) (2−y) dy=2y−(y^2 /2) ∣_0 ^(√(4−x))   ∫_0 ^4 2(√(4−x))−(((4−x))/2)  2×(((−2)/3))((√(4−x)))^3 −2x+(x^2 /4) ∣_0 ^4   0−2×4+(4^2 /4)−(2×(((−2)/3))(√(4−0))^3 )  6.666667=((20)/3)

$$\mathbb{D}=\left\{\left(\boldsymbol{\mathrm{x}},{y},{z}\right)/\mathrm{0}\ll{x}\ll\mathrm{4};\right. \\ $$$$\mathrm{0}\ll{y}\ll\sqrt{\mathrm{4}−{x}}\:\:; \\ $$$$\mathrm{0}\ll{z}\ll\mathrm{2}−{y} \\ $$$${x}\:{is}\:{variable}\:{free} \\ $$$$\int_{\mathrm{0}} ^{\:\mathrm{4}} \int_{\mathrm{0}} ^{\sqrt{\mathrm{4}−{x}}} \int_{.\mathrm{0}} ^{\mathrm{2}−{y}} {dzdydx} \\ $$$$\int_{\mathrm{0}} ^{\sqrt{\mathrm{4}−{x}}} \left(\mathrm{2}−{y}\right)\:{dy}=\mathrm{2}{y}−\frac{{y}^{\mathrm{2}} }{\mathrm{2}}\:\mid_{\mathrm{0}} ^{\sqrt{\mathrm{4}−{x}}} \\ $$$$\int_{\mathrm{0}} ^{\mathrm{4}} \mathrm{2}\sqrt{\mathrm{4}−{x}}−\frac{\left(\mathrm{4}−{x}\right)}{\mathrm{2}} \\ $$$$\mathrm{2}×\left(\frac{−\mathrm{2}}{\mathrm{3}}\right)\left(\sqrt{\mathrm{4}−{x}}\right)^{\mathrm{3}} −\mathrm{2}{x}+\frac{{x}^{\mathrm{2}} }{\mathrm{4}}\:\mid_{\mathrm{0}} ^{\mathrm{4}} \\ $$$$\mathrm{0}−\mathrm{2}×\mathrm{4}+\frac{\mathrm{4}^{\mathrm{2}} }{\mathrm{4}}−\left(\mathrm{2}×\left(\frac{−\mathrm{2}}{\mathrm{3}}\right)\sqrt{\mathrm{4}−\mathrm{0}}\:^{\mathrm{3}} \right) \\ $$$$\mathrm{6}.\mathrm{666667}=\frac{\mathrm{20}}{\mathrm{3}} \\ $$$$ \\ $$$$ \\ $$$$ \\ $$$$ \\ $$$$ \\ $$

Terms of Service

Privacy Policy

Contact: info@tinkutara.com