Calculate the surface area Integral of object obtained by rotating the function x=2y+5 for x=-1 and -2 about y axis
1
Expert's answer
2022-04-20T14:52:50-0400
If the curve x=x(y) is rotated around y-axis, the formula for the surface area is: S=2π∫y1y2x(y)1+(x′(y))2dy. In our case we have: x=2y+5,y1=−3,y2=−3.5. We get: S=2π∫−3−3.55(2y+5)dy=2π5(y2+5y)∣y=−3y=−3.5=23π5 . Thus, the answer is: S=23π5.
Comments