Respuesta :

We are given with the equation
y = e^-9x with the restriction of x ≥ 0
If rotated about the x-axis the area of the resulting surface is
A = 
π ∫ y² dx
Substituing
A = π ∫ (e^-9x)² dx
A = π ∫ e^-18x dx
The limits are from 0 to positive infinity.
Q&A Education