For which kkk is x2+kx+1>0x^2 + kx + 1 > 0x2+kx+1>0 for all xxx?
∣k∣<2|k| < 2∣k∣<2
∣k∣>2|k| > 2∣k∣>2
k>1k > 1k>1
k<−1k < -1k<−1