Question

Derivative of y=xsiny

Answer 1

I got this
y'= siny+x(-cosy)(y')
=siny-xcosy

Answer 2

derivative of siny is not -cosy, woops! :OOO

Answer 3

oh... it would siny+xcosy? @zepdrix

Answer 4

hmm no.

Answer 5

\[\Large\rm y'=\sin y+(x \cos y) y'\]This step looks ok once we fix the minus sign.

Answer 6

Your y' disappeared from the cosine in your next step though! D: woahhh

Answer 7

I'm not sure what to do with it...

Answer 8

You need to do some factoring!! :)
Let's subtract (xcosy)y' to the others side.

Answer 9

\[\Large\rm y'-(x \cos y)y'=\sin y\]What next? :)
Remember?

Answer 10

Common factor...

Answer 11

Oh I see it would this:
\[y'=\frac{ siny }{ 1-xcosy }\]

Answer 12

yeaaaa there we go!

Answer 13

Thanks again!