(x+3)+(5x-2x)

To simplify the expression \((x + 3) + (5x - 2x)\), follow these steps:

1. Simplify the term inside the parentheses:
   \(5x - 2x = 3x\).

2. Now substitute back into the expression:
   \((x + 3) + 3x\).

3. Combine like terms:
   \(x + 3x + 3 = 4x + 3\).

Thus, the simplified expression is:
\(\mathbf{4x + 3}\).