Chapter 5 - Section 5.4 - Indefinite Integrals and the Net Change Theorem - 5.4 Exercises - Page 415: 18

$2x + \frac{{{3^x}}}{{\ln 3}} + C$

$$\eqalign{ & \int {\left( {2 + {3^x}} \right)} dx \cr & {\text{Use the sum rule for integration}} \cr & = \int 2 dx + \int {{3^x}} dx \cr & {\text{From the table of indefinite integrals }} \cr & \int c dx = cx + C{\text{ and }}\int {{b^x}} dx = \frac{{{b^x}}}{{\ln b}} + C \cr & {\text{Then}}{\text{,}} \cr & \int 2 dx + \int {{3^x}} dx = 2x + \frac{{{3^x}}}{{\ln 3}} + C \cr} $$