Hei! :)
[tex]3,5^{2} -1,5^{3} =\\=(\frac{35}{10} )^{2} -(\frac{15}{10} )^{3} =\\=(\frac{7}{2} )^{2} -(\frac{3}{2} )^{3} =\\=\frac{49}{4} -\frac{27}{8} =\\=\frac{98}{8} -\frac{27}{8} =\\=\frac{71}{8} =8,875[/tex]
