Quick question. [tex]sin(-x) = -sin(x)[/tex] this can be seen as this example: [tex]sin(i^2x) = i^2sin(x)[/tex] Does this then apply? [tex]sin(ix) = isin(x)[/tex] ? I'm trying to derive a formula for the length of a simple parabola. Unfortunetly in my calculations I end up with Arcsin(i2x) along the way and it would make my life alot simpler if that could be treated as iArcsin(2x). Then the i would be divided out and then I'd get a real number instead of a complex number. It's sort of a dare, I'm taking the calculus course where we learn about complex numbers but I read the book during the christmas vacation so I've got most of the basics down. Right now we're learning about the length of functions and we asked if our teacher would give us an example using a parabola of the form Ax^2 + C, but she said it was too complex. Of course, once she says that we spend the rest of the week trying to do it by ourselfes. Thanks a lot.