- (a) Find the first four terms, in ascending powers of \(x\), of the binomial expansion of
$$\sqrt { 4 - 9 x }$$
writing each term in simplest form.
A student uses this expansion with \(x = \frac { 1 } { 9 }\) to find an approximation for \(\sqrt { 3 }\)
Using the answer to part (a) and without doing any calculations,
(b) state whether this approximation will be an overestimate or an underestimate of \(\sqrt { 3 }\) giving a brief reason for your answer.