Differentiation was ok - but you should now

*simplify*.

Differentiation is not ok. Where on earth did you get that factor

? The second factor was

, no?

And, again, you need to simplify.

Almost, but not quite: everything seems ok except the term

. Think about it. Did you apply the power rule correctly? I don't think so.

Looks ok to me, but maybe one would want to ask whether some simplification is possible. Well, maybe - or maybe not.

Differentiation seems ok, but what about simplifying the whole mess? After all one might be able to collect same powers of x.

is a polynomial of degree 6, therefore

must be a polynomial of degree

. I think it should be possible to make a polynomial of degree 5 look a little tidier on the page than this...

Differentiation seems ok to me. (I'm a little surprised to see you put the "inner derivative"

as the second factor here.) I don't think one would want to try to "simplify" here by multiplying out

No, for some reason you have botched this one up completely. What about

Now here, you would simplify by factoring out

Judging from the above, you should be able to differentiate this one as well.