does barbie count??

( Steerable_forehead Bring back Kickstart, Mon 9 Jun 2003, 15:01, archived)

can someone differentiate
1-cos a=y
a-sin a=x

for me... preferably with workings :)
( lemony, Mon 9 Jun 2003, 15:04, archived)

Here you go:
1-cos a=y is the one with the =y at the end.
a-sin a=x is the one with the =x at the end.

Oh wait, you meant a different kind of differentiate, didn't you?
(OB1, Mon 9 Jun 2003, 15:08, archived)

badum
tsch
( lemony, Mon 9 Jun 2003, 15:08, archived)

I'm very rusty, but this might do?
dy/da = sin a
dx/da =1 +cos a
dy/dx = sin a / 1+ cos a
dy/dx = x -a / 2- y
dy/dx = (x - cos^-1 (1-y)) / 2-y

I'm sure there's a better way though. Please post a kitten as payment.
(WouldSwapABearForATiger, Mon 9 Jun 2003, 15:21, archived)

OK done it
I had to make a CORDIC engine out of lego though.

If you want the workings I have them in a placky bag
( Oscar Wildebeest, Mon 9 Jun 2003, 15:23, archived)

You haven't said
with respect to what you want them differentiated.

If y = 1 + cos a
then dy/da = -sin a
but dy/dx = 0 (y is constant wrt x)

I know in your case it's fairly obvious but if you're gonna get to the stage of really understanding this stuff it's probably worth noting.
( Hagbard - Mario Kart DS Code in profile, Mon 9 Jun 2003, 15:28, archived)