How many real and imaginary roots does the equation y2=x3-4x have
(a) 2 real, 1 imaginary
(b) all real
(c) all imaginary
(d) 2 imaginary, 1 real
The question was posed to me during an internship interview.
My question is taken from Elliptic Curve Arithmetic/Cryptography topic in portion Other Public Key Cryptosystems and Cryptographic Hash Functions of Cryptograph & Network Security