Find the first 3 terms, in ascending powers of x, of the binomial expansion of (2 − 9x)4 giving each term in its simplest form.
f(x) = (1 + kx)(2 − 9x)4, where k is a constant
The expansion, in ascending powers of x, of f(x) up to and including the term in x2 is
where A and B are constants. (b) Write down the value of A.
(c) Find the value of k.
(d) Hence find the value of B.