How to graph manually the rational functions of the form $f(x)=\frac{x+1}{2x^2+1}$

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How to plot function of the form $f(x)= \dfrac{x+1}{2x^2+1}$ manually

What are the functions of this type called? Is it a quadratic function?

Edit ..Thanks for letting me know that functions of this form are called rational functions

Please help me. I am new to this.

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Hint for the plot: Here are some things one typically looks for:

  1. Intersections with axes. To obtain these, we solve:

    $$f(0)=y, \text{ and } f(x)=0,$$ for $x$ and $y$ respectively.

2.1 Local monotonicity. For this one simply takes the derivative of $f$ with respect to $x$ and determines the sub-domains in which the function increases/decreases.

2.2. Turning points . Points in which $f'(x)=0$ and such that $f'(x)$ "changes sign" (thanks @Henry).

  1. Local convexity/concavity. For that, we study the second derivative of $f$ with respect to $x$ and solves the inequalities $f''(x)<0$ and $f''(x)>0$

  2. Limits. Compute $\lim_{x\to \infty}f(x)$ and $\lim_{x\to -\infty}f(x)$.

  3. Discontinuities. Look for possible discontinuities in the domain of $f$.

Can you determine these for your function of interest?