The function f(x)f(x)f(x) is given by f(x)=1−3xf(x) = \sqrt{1 - 3x}f(x)=1−3x, so that a=−3a=-3a=−3.
Using this value of aaa, state the set of values for which the binomial expansion is valid.
408 exam-style questions on Edexcel A Level Maths Binomial Expansion, covering 4.1 Expanding (1 + x)^n, 4.2 Expanding (a + bx)^n, and 4.3 Using Partial Fractions. Each one has a worked solution and a mark scheme showing where the marks go.