If x2−4x+k2−2k=0x^2 - 4x + k^2 - 2k = 0x2−4x+k2−2k=0 has no real roots, then:
k2−2k−4<0k^2 - 2k - 4 < 0k2−2k−4<0
k2−2k−4>0k^2 - 2k - 4 > 0k2−2k−4>0
k2−2k+4<0k^2 - 2k + 4 < 0k2−2k+4<0
k2−2k+4>0k^2 - 2k + 4 > 0k2−2k+4>0