It seems like you want to simplify a complex expression, but it's a bit unclear how the terms are related. Based on what you've written, I assume you're referring to the square roots of negative numbers, possibly:

$\sqrt{-18} - \sqrt{-1} - \sqrt{-16}$

In this case, we can simplify each square root of the negative numbers by using the imaginary unit $i$, where $i = \sqrt{-1}$.

Let's break it down:

1. $\sqrt{-18} = \sqrt{18} \cdot i = 3\sqrt{2} \cdot i$
2. $\sqrt{-1} = i$
3. $\sqrt{-16} = \sqrt{16} \cdot i = 4 \cdot i$

Now we can rewrite the expression:

$3\sqrt{2}i - i - 4i$

Combine the imaginary terms:

$3\sqrt{2}i - (1 + 4)i = 3\sqrt{2}i - 5i$

Thus, the simplified expression is:

$3\sqrt{2}i - 5i$

This is the simplified form of the original expression.

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Would you like more details on simplifying complex numbers or operations with imaginary numbers?

Here are 5 related questions:

1. What are the basic rules for working with imaginary numbers?
2. How do you add or subtract complex numbers?
3. How can you simplify higher-order square roots of negative numbers?
4. What is the geometric representation of complex numbers on the complex plane?
5. How do you multiply or divide complex numbers?

Tip: When simplifying complex expressions, always try to factor out the imaginary unit $i$ to make the calculations easier!