Let `C` be the curve `y = 4 sqrt( x )` for `2.8 le x le 4.3`.

Find the surface area of revolution about the `x`-axis of `C`.

Surface area `= int_2.8^4.3 f( x ) \ dx` where

`f( x ) =`  

Write your answer in this format: `2 pi * 4 sqrt( x + 4^2 / 4 )`

Now integrate to find surface area

Surface area `= int_2.8^4.3 f( x ) \ dx =`  

Hint

Box 1: Enter your answer as an expression. Example: 3x^2+1, x/5, (a+b)/c
Be sure your variables match those in the question

Box 2: Enter your answer as a number (like 5, -3, 2.2172) or as a calculation (like 5/3, 2^3, 5+4)
Enter DNE for Does Not Exist, oo for Infinity