Mathematics

Problem

For what values of

t

does the equation

x^{2} - 4tx + (t + 5) = 0

have no real roots? a)

-1 \le t \le \dfrac{5}{4}

t < -1 \text{ or } t > \dfrac{5}{4}

-1 < t < \dfrac{5}{4}

t = -1 \text{ or } t = \dfrac{5}{4}