1. The function f(x,y) = x + y 2. The area A is formed by the lines : x = 0 and x = pi/4 and by the graphs : x + cos(x) and x + sin(x) 3. I have to parametrize A 4. 'Formula' : r(u,v) = (u,v*f(u)+(1-v)*g(u)) Could this be a parameterization of A : assuming f(u) = u+ cos(u) and g(u) = u + sin(u) r(u,v) = (u, v*(u+cos(u))+(1-v)*(u+sin(u))) <-> r(u,v) = (u, v*cos(u)+u+sin(u)-v*sin(u)) and http://mathhelpforum.com/attachments/calculus/27437d1362743750-integration-flat-area-parameterization-billede-2.png ? ? ? I would really appreciate it if someone could look at this and give me some feedback because I'm not sure if the parametrization is correct :/ and I cannot solve the rest of the problem if the parametrization is incorrect.