Mathematics - Functions Question with Solution | TestHub

Let $f(x)=ax+b$ where a and b are rational numbers (where $b\ne 0$ ). Such that $f(1)\le f(2)$, $f(3)\ge f(4)$ then value of $\left(\frac{{\sum }_{r=1}^{2n-1}f(\sqrt{2}r)}{f(\sqrt{3})}\right)($ where $n\in \mathbb{N})$ is