Answer:
(0,-3)
Step-by-step explanation:
2x-y = 3
x+2y = -6
Multiply the first equation by 2 so we can eliminate y
2(2x-y =3)
4x -2y = 6
Add this to the second equation
4x -2y = 6
x+2y = -6
-----------------
5x +0y = 0
x = 0
Now find t
x+2y = -6
0+2y = -6
2y =-6
Divide by 2
y = -3
It comes from integrating by parts twice. Let

Recall the IBP formula,

Let


Then

Apply IBP once more, with


Notice that the ∫ v du term contains the original integral, so that




Answer:
V = 128π/3 vu
Step-by-step explanation:
we have that: f(x)₁ = √(4 - x²); f(x)₂ = -√(4 - x²)
knowing that the volume of a solid is V=πR²h, where R² (f(x)₁-f(x)₂) and h=dx, then
dV=π(√(4 - x²)+√(4 - x²))²dx; =π(2√(4 - x²))²dx ⇒
dV= 4π(4-x²)dx , Integrating in both sides
∫dv=4π∫(4-x²)dx , we take ∫(4-x²)dx and we solve
4∫dx-∫x²dx = 4x-(x³/3) evaluated -2≤x≤2 or too 2 (0≤x≤2) , also
∫dv=8π∫(4-x²)dx evaluated 0≤x≤2
V=8π(4x-(x³/3)) = 8π(4.2-(2³/3)) = 8π(8-(8/3)) =(8π/3)(24-8) ⇒
V = 128π/3 vu