If the ellipse $\frac{{\mathrm{x}}^2}{4}+{\mathrm{y}}^2=1$ meets the ellipse ${\mathrm{x}}^2+\frac{{\mathrm{y}}^2}{{\mathrm{a}}^2}=1$ at four distinct points and $\mathrm{a}={\mathrm{b}}^2–5\mathrm{b}+7$ then 'b' does not lie in