The shell has the radius -2 - y , the cricumference is 2pi*(-2 - y) and the height is 2 - x , hence, the volume can be evaluated, using the method of cylindrical shells, such that:
V = 2pi*int_(y_1)^(y_2) (-2 - y)*(2-x) dy
You need to evaluate the endpoints from equation y^2+1=2 => y^2 = 1 => y_(1,2) = +-1
V = 2pi*int_(-1)^1 (-2 - y)*(2 - y^2 - 1) dy
V = 2pi*int_(-1)^1 (-2 - y)*(1 - y^2) dy
V = 2pi*int_(-1)^1 (-2 + 2y^2 - y + y^3)dy
V = 2pi*(int_(-1)^1 (-2 dy) + int_(-1)^1 2y^2 dy - int_(-1)^1 ydy + int_(-1)^1 y^3 dy)
Using the formula int x^n dx = (x^(n+1))/(n+1) yields:
V = 2pi*(-2y + 2y^3/3 - y^2/2 +y^4/4)|_(-1)^1
V = 2pi*(-2 + 2/3 - 1/2 + 1/4 + 2 +2/3 + 1/2 - 1/4)|_(-1)^1
V = 2pi*(+ 4/3)
V = (8pi)/3
Hence, evaluating the volume, using the method of cylindrical shells, yields V = (8pi)/3.
Thursday, March 8, 2018
Calculus: Early Transcendentals, Chapter 6, 6.3, Section 6.3, Problem 20
Subscribe to:
Post Comments (Atom)
Summarize the major research findings of "Toward an experimental ecology of human development."
Based on findings of prior research, the author, Bronfenbrenner proposes that methods for natural observation research have been applied in ...
No comments:
Post a Comment