question 9 and 10 (2 Viewers)

[rama_v]

For those massive factorisations would it be smart to start substituting values in to get a simpler expression, then take care of the differentiation outside of the equation ?!

huh?
Differentiate it first before simplifying if u can, since usually they leave it in a form thats easy(er) to differentiate. Whatever happens, dont make the question harder than it already is