Yefim S. answered 10/22/20
Math Tutor with Experience
All 3 graphs passing throut point (1,6) and 2 graphs passing point (2,0). So we have for region R:
1 ≤ x ≤ 2, 6sin(πx/2) ≤ y ≤ 4x + 2
2 ≤ x ≤ 11/3, 6(x - 2)2 ≤ y ≤ 4x + 2
Rotation about x-axi by disk metod: v = π∫12[(4x + 2)2 - 36sin2(πx/2)]dx + π∫211/3[(4x + 2)2 - 36(x - 2)4]dx =
148.7 + 659.35 = 808.05 I use TI-84 to evaluate integrals
Rotation about y-axis, by Shell method: V = 2π∫12x[4x + 2 - 6sin(πx/2]dx + 2π∫211/3x[4x + 2 - 6(x - 2)2]dx =
44.77 + 216.23 = 260.00
Now volume if R is base V= ∫12(4x + 2 - 6sin(πx/2))2dx + ∫211/3(4x + 2 - 6(x - 2)2)2dx = 26.39 + 117.28 = 142.67;
All integrals evaluated by TI-84. I think that goal of this problem to setup these integrals