Find the first three terms, in ascending powers of xxx, of the binomial expansion of (2+kx)6(2 + kx)^6(2+kx)6 where kkk is a constant. Give each term in simplest form.
The population PPP of a bacterial culture is modeled for small time intervals xxx by the expression (5−2.5x)(2+kx)6(5 - 2.5x)(2 + kx)^6(5−2.5x)(2+kx)6 where kkk is a growth constant. Given that the coefficient of x2x^2x2 in the expansion of this expression is 606060, find the possible values of kkk.
Practise Edexcel A Level Maths 4.2 Expanding (a + bx)^n with exam-style questions for A Level Maths. 99 questions, matched to the Edexcel A Level Maths (9MA0) specification and written in Paper 1, Paper 2 and Paper 3 style. Every question includes a full worked solution and mark scheme, so you can see where marks are awarded rather than just whether you got the answer right.