Answer
The first 3 terms are:
$x^{40}$
$40x^{38}$
$780x^{36}$
Work Step by Step
We find the first 3 terms in the expansion of $(x+ \frac{1}{x})^{40}$ by using Binomial Theorem coefficients:
$\left(\begin{array}{l} 40\\ 0\end{array}\right)x^{40}(\frac{1}{x})^0=x^{40}$
$\left(\begin{array}{l}
40\\ 1 \end{array}\right)x^{39}(\frac{1}{x})^1=40x^{38}$
$\left(\begin{array}{l} 40\\ 2 \end{array}\right)x^{38}(\frac{1}{x})^{2}=780x^{36}$
