Answer:
Here's what I get
Step-by-step explanation:
a) x² = x - b
I plotted the graphs of y = x² - x + b with different values of b and found:
[tex]\begin{cases}\text{0 real roots} & \quad \text{if } b < 0.25 \\\text{1 real root}& \quad \text{if } b = 0.25\\\text{2 real roots}& \quad \text{if } b > 0.25\\\end{cases}[/tex]
You can see three specific cases in Fig.1.
b) x² = bx - 1
I plotted the graphs of y = x² - bx + 1 with different values of b and found:
[tex]\begin{cases}\text{2 real roots} & \quad \text{if } b \text{ is on the interval } (-\infty, -2) \cup (2,\infty) \\\text{1 real root}& \quad \text{if } b = -2 \text{ or } 2\\\text{0 real roots}& \quad \text{if } b \text{ is on the interval (-2,2)}\\\end{cases}[/tex]
You can see five specific cases in Fig. 2.