b)
[tex](\frac{4}{5})^{2} -\frac{4^{2}}{5}+\frac{4}{5^{2}} = \frac{16}{25}-\frac{16}{5}+\frac{4}{25} = \frac{16}{25}+\frac{4}{25}-\frac{80}{25} = \frac{20}{25}-\frac{80}{25} = -\frac{60}{25}=-\frac{12}{5} = -2\frac{2}{5}[/tex]
