16x^2-1

\frac{49}{4}x^2-\frac{4}{25}

\frac{9}{25}x^2+\frac{12}{25}x+\frac{4}{25}

4x^2+16x+16

\frac{1}{25}x^2+\frac{14}{15}x+\frac{49}{9}

x^2+4x+4

x^2-81

81x^2-9

5x^2-12\sqrt{5}x+36

\frac{36}{25}x^2-\frac{1}{9}

11x^2-14\sqrt{11}x+49

7x^2-16\sqrt{7}x+64

\frac{81}{4}x^2-\frac{4}{25}

11x^2-4\sqrt{11}x+4

4x^2+40x+100

\frac{4}{9}x^2-\frac{28}{9}x+\frac{49}{9}

5x^2+14\sqrt{5}x+49

81x^2+162x+81

\frac{1}{4}x^2-\frac{81}{25}

25x^2+60x+36

\frac{1}{16}x^2+\frac{3}{5}x+\frac{36}{25}

\frac{1}{25}x^2-\frac{2}{45}x+\frac{1}{81}

x^2-1

\frac{1}{4}x^2-\frac{2}{9}x+\frac{4}{81}

4x^2+20x+25