3. Answer this question without a calculator, showing all your working and giving your answers in their simplest form.
- Solve the equation
$$4 ^ { 2 x + 1 } = 8 ^ { 4 x }$$
- (a) Express
$$3 \sqrt { 18 } - \sqrt { 32 }$$
in the form \(k \sqrt { 2 }\), where \(k\) is an integer.
(b) Hence, or otherwise, solve
$$3 \sqrt { 18 } - \sqrt { 32 } = \sqrt { n }$$