Bernoulli lemniskaat ja Cassini ovaal

a = 3.4 (slider from -5 to 5)
lem: (x^(2) + y^(2))^(2) = ((2 * a^(2)) * (x^(2) - y^(2)))
b = 3.1 (slider from -5 to 5)
cass: (((x - a)^(2) + y^(2)) * ((a + x)^(2) + y^(2))) = b^(4)