not much trouble by the way
but a slight mistake
if u=cos2x
than d(u)=-sin2xd(2x)
=-2sin2xdx
but i don't really know why u r making this substitution?
cos2x is a basic integration, but if u want to do it this way which is useless than do tell i will tell u than how to do this useless thing
it is the question which has baffled me since i took vector analysis.
later somewhere i read that r.p.feynman too tried to dwell in it.i have post this thread in physics forum a year before and there were many replies. but not with that mathematical presicion .enpugh of background, now my...
we all know abt twin paradox(except those poor souls who would rather read playboy than physics today!)
now a very fundamental question abt it is;
does time really gets slow when we r moving with speed comparable to that of light or its just 'malefunctioning'(mark the word) of clocks?
what i...