a)
16
16=4^2 i (-4)^2
b) 900
900=30^2 i (-30)^2
c) 81
81=9^2 i (-9)^2
d) 1
1=1^2 i (-1)^2
e) 1/4
\frac{1}{4}=(\frac{1}{2})^2 i (-\frac{1}{2})^2
f) 4/49
\frac{4}{49}=(\frac{2}{7})^2 i (-\frac{2}{7})^2
g) 0,36
0,36=0,6^2 I -0,6^2
h) 1.21
1,21=\frac{121}{100}=(\frac{11}{10})^2=1,1^2 i -
i) 3 i 1/16 1,1^2
3\frac{1}{16}=\frac{49}{16}=(\frac{7}{4})^2=(1\frac{3}{4})^2 i (-1\frac{3}{4})^2
j) 11 i 1/9
11\frac{1}{9}=\frac{100}{9}=(\frac{10}{3})^2=(3\frac{1}{3})^2 i (-3\frac{1}{3})^2