SOLUTION: For how many integers b does the inequality z^2 + bz + 15

SOLUTION: For how many integers b does the inequality z^2 + bz + 15 < 0 have no real solutions z?

Question 1030084: For how many integers b does the inequality z^2 + bz + 15 < 0 have no real solutions z?
Answer by richard1234(7193) (Show Source): You can put this solution on YOUR website!
You want the discriminant to be negative or zero so that the graph of z^2 + bz + 15 lies completely above the z-axis (i.e. is always non-negative).

Therefore we want

. This works for

or 15 integers.
RELATED QUESTIONS
Construct the quadratic equation in the form az2+bz+c =0 having the following solutions.... (answered by solver91311)

bz-cd/a=z solve for... (answered by Fombitz)

How many and what type of solutions does the equation have? �4x^2 � 2 = 10x A. no real... (answered by fractalier)

How many and what type of solutions does the equation have? 5y^2 = 18y � 4 A. no real... (answered by rothauserc)

Can you please help me with those problems??? 1. Suppose that |a - b| + |b - c| + |c - (answered by chessace)

Solve the inequality: -8(z-6) less than or equal to -8z-7 a) z is less than or equal... (answered by stanbon)

How many real number solutions does the equation 0=4x^2+9... (answered by richwmiller)

Consider the following final tableau corresponding to a linear programming problem. x (answered by Edwin McCravy)

The roots of the quadratic equation z^2 + bz + c = 0 are 5 + 3i and -2 + 7i. What is b + (answered by ikleyn)