Posted by Subhotosh khan on August 29, 2002 at 12:53:05:
In Reply to: Need help desperately - seems like a simple integral? posted by Dartchen on August 29, 2002 at 12:00:30:
: Was given a problem that originally seemed simple but I think I'm making some conceptual errors on.
: integral tan(x^1/2)dx
: My original thoughts on the solution would be substitution
: x^1/2 = u
du = 1/2*x^(-1/2)dx = 1/(2u)dx
dx = 2*u du
: 2 integral[u* (sin(u)/cos(u))]du )
Now of course rest of your "integration" need to be changed.
: cos(u) = t
: dt = -sin(u)du
: sooo... -2integral dt/t = -2ln|t|+C
: -2ln|cos(u)|+C
: -2ln|cos(x^1/2)|+C ??
: I'm probably way off but any hints/help would be GREATLY appreciated!!
: Thanks!!