Find the surface area of the cone z=3x^2+y^2and above a region in the xy-plane with area 4.
double integral sqrt( (dz/dx)^2 + (dz/dy)^2 +1)
The Attempt at a Solution
I was able to simplify the equation, I just don't know what to do with the area part of the question:
dbl int sqrt ( (3x/sqrt(x^2+y^2))^2 + (3y/sqrt(x^2+y^2))^2 + 1)
dbl int sqrt (9 (x^2+y^2)/(x^2+y^2) + 1 )
dbl int sqrt (10)
change into polar coordinates
integral [0-1] dtheta integral [0-2pi] sqrt(10) r dr
= 1*2pi sqrt(10)
what am I doing wrong?