Can somebody me? and explain how to do this?

The correct answer is last option

2n + m√n - nm

Step-by-step explanation:

It is given an expression,

4√n² + √m²n -  √4n² - √mn²

To simplify the expression

4√n² + √m²n -  √4n² - √mn² = 4n + m√n -2n -nm

= 4n - 2n + m√n - n√m

= 2n +  m√n - n√m

Therefore the correct answer is last option

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