What is the surface area of the solid created by revolving f(x) = 2x^2-4x+8 , x in [1,2]f(x)=2x2−4x+8,x∈[1,2] around the x axis?
1 Answer
May 29, 2016
approximately
Explanation:
The surface area
S=2piint_a^bf(x)sqrt(1+[f'(x)]^2)dx
Using
S=2piint_1^2(2x^2-4x+8)sqrt(1+(4x-4)^2)dx
Actually integrating this is very complex and far beyond the scope of this problem, so put this into a calculator--be mindful of parentheses.
The answer you receive (don't forget to multiply by
Sapprox100.896