Question Number 179344 by neinhaltsieger369 last updated on 28/Oct/22

Commented by CElcedricjunior last updated on 29/Oct/22
![k=∫_0 ^𝛑 ∫_0 ^(3cos∅) 𝛉sin∅d𝛉d∅ k=∫_0 ^𝛑 sin∅[(1/2)𝛉^2 ]_0 ^(3sin∅) d∅ k=(9/2)∫_0 ^𝛑 sin^3 ∅d∅=(9/2)∫_0 ^𝛑 (sin∅−sin∅cos^2 ∅)d∅ k=(9/2)[−cos∅+((cos^3 ∅)/3)]_0 ^𝛑 =(9/2)(1−(1/3)) k=3 d′ou^� ∫_0 ^𝛑 ∫_0 ^(3sin∅) 𝛉sin∅d𝛉d∅= 3 um ..............le celebre cedric junior........](https://www.tinkutara.com/question/Q179466.png)
Commented by neinhaltsieger369 last updated on 01/Nov/22

Answered by mr W last updated on 28/Oct/22
![=∫_0 ^π sin φ(∫_0 ^(3 cos φ) θdθ)dφ =∫_0 ^π sin φ(((9 cos^2 φ)/2))dφ =−(9/2)∫_0 ^π cos^2 φd(cos φ) =−(9/2)[((cos^3 φ)/3)]_0 ^π =(3/2)[1−(−1)] =3](https://www.tinkutara.com/question/Q179359.png)
Commented by neinhaltsieger369 last updated on 29/Oct/22
