## Step-by-step Solution

Problem to solve:

Solving method

Learn how to solve integrals of exponential functions problems step by step online.

$3\int e^x\cdot xdx$

Learn how to solve integrals of exponential functions problems step by step online. Find the integral int(3e^x*x)dx. The integral of a constant by a function is equal to the constant multiplied by the integral of the function. We can solve the integral \int e^x\cdot xdx by applying integration by parts method to calculate the integral of the product of two functions, using the following formula. First, identify u and calculate du. Now, identify dv and calculate v.