- (a) Find the binomial expansion of
$$\sqrt { } ( 9 + 8 x ) , \quad | x | < \frac { 9 } { 8 }$$
in ascending powers of \(x\), up to and including the term in \(x ^ { 2 }\).
Give each coefficient as a simplified fraction.
(b) Use your expansion to estimate the value of \(\sqrt { } ( 11 )\), giving your answer as a single fraction.