a parameterization for a surface called a helicoid is given: f(s,t)= (scost,ssint,t)
compute the surface area of the helicoid corresponding to (s,t): [0,1]x[0,2pi]
sorry i'm completely lost on this problem..any ideas how to set it up?
Usually we have the surface given parametrically as
$\displaystyle
{\bf r} = {\bf r}(u,v)
$
and the surface area is given by
$\displaystyle \iint_R || {\bf r_u \times r_v } || dA\,\, (1)$
Here, we have
$\displaystyle
{\bf f} = < s \cos t,s \sin t,t>
$
so identify $\displaystyle {\bf r = f},\;\;u = s$ and $\displaystyle v = t$ and follow (1)