Which of the following must be true about b?

Which of the following must be true about b?

In the xy-plane, the graph of the function f(x) = x² + bx + 4 does not intersect the x-axis. Which of the following must be true about b?

• −8 ≤ b< −4
• b = −4
• −4 < b< 4
• b= 4
• 4 < b ≤ 8

Last Updated on February 11, 2019