Expanding Brackets

How do you do these find of questions where you have to expand brackets with powerof 4

I have expanded but got x^4 + 4x^3h + 6 h^2x^2 + 4xh^3 +h^4
Is this correct?

And how do you answer questions like part 5ii) C) and why doesit mean that it is the gradient to the tangent ?

http://pmt.physicsandmathstutor.com/download/Maths/A-level/C2/Topic-Qs/OCR-MEI/C2%20Differentiation%20-%20Basic%203%20QP.pdf

Answer:http://pmt.physicsandmathstutor.com/download/Maths/A-level/C2/Topic-Qs/OCR-MEI/C2%20Differentiation%20-%20Basic%203%20MS.pdf

Yes.
You use binomial expansion. Or Pascal's triangle. Whatever works for you best.


Tangent to the curve at $x$, rather you mean.
I've answered this at least three times before for you + this is part of your theory if it's in the exam, so I can't be bothered repeating myself once more. Look it up.

In the mark scheme, the expanded form does not have some of the terms in my expansion
The mark scheme is 6x^2h^2 + 4xh^3 + h^4
But my answer is x^4 + 4x^3h + 6 h^2x^2 + 4xh^3 +h^4