7) \( 3 \sqrt{3}-\sqrt{3}-2 \sqrt{2} \)

To simplify the expression \( 3 \sqrt{3} - \sqrt{3} - 2 \sqrt{2} \), start by combining like terms. Notice that \( 3 \sqrt{3} - \sqrt{3} \) can be simplified to \( (3-1) \sqrt{3} = 2\sqrt{3} \). Thus, you get: \[ 2\sqrt{3} - 2\sqrt{2} \] Now, you may factor out the 2: \[ 2(\sqrt{3} - \sqrt{2}) \] That's your simplified expression! Feel free to experiment with this expression, trying to approximate the values of \( \sqrt{3} \) and \( \sqrt{2} \) to explore the numerical results. For instance, using \( \sqrt{3} \approx 1.732 \) and \( \sqrt{2} \approx 1.414 \), you can get an approximate numerical result for \( 2(\sqrt{3} - \sqrt{2}) \).