Sure, let's solve this step by step:

a. To show that m + n = 2/2 + √3, we simply add m and n:

m + n = (2 - √3) + (1/2 + √3)

Simplify the above expression:

m + n = 2 - √3 + 1/2 + √3

The √3 terms cancel out, and we get:

m + n = 2 + 1/2 = 2.5

So, m + n is not equal to 2/2 + √3 (which is 1 + √3). There seems to be a mistake in the question.

b. To express m + n in the form a - b√c by rationalising the denominator, we first need to have a term with a square root in the denominator. However, in this case, m + n = 2.5, which is already a rational number. So, it doesn't need to be rationalised.

Please check the question again. It seems there might be a mistake in it. If you have any other questions or need further clarification, feel free to ask!

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