Resposta:

Explicação passo a passo:

3.

a)

[tex](1\frac{1}{4} )^2+(-0,25)^2=\\\\=(\frac{5}{4})^2+(-\frac{1}{4}) ^2=\\\\=\frac{5^2}{4^2} +\frac{1^2}{4^2} =\\\\=\frac{25+1}{16} =\frac{26}{16}=\frac{13}{8}[/tex]

b)

[tex]\frac{(-0,25)^2}{(-0,75)^2} =\\\\=(-\frac{25}{100})^2 *(-\frac{100}{75} )^2=\\\\=(-\frac{1}{4})^2*(-\frac{4}{3} )^2=\\\\=\frac{1}{16} *\frac{16}{9} =\frac{16}{144} =\frac{1}{9}[/tex]

c)

[tex](\frac{1}{4})^{-1}*(-\frac{1}{8})^0=\\\\=\frac{4}{1}*1=\frac{4}{1}[/tex]

Obs.: Todo numero elevado a zero é 1!