Find the range of kkk for which x2+kx+4=0x^2 + kx + 4 = 0x2+kx+4=0 has no real solutions.
−4<k<4-4 < k < 4−4<k<4
k>4k > 4k>4 or k<−4k < -4k<−4
k<4k < 4k<4
k>−4k > -4k>−4