Step 1 :

If a smooth parametric surface S is given by the equation

and S is covered just once as ranges throughout the parameter domain , then the surface area of S is ,

where .

Step 2 :  

Evaluate .

Here ,

Step 3 :

.

Consider

.

Differentiate the above equation partially with respect to u .

.

Consider

.

Differentiate the above equation partially with respect to v .

.

Step 4:

Thus, .