(0,5а-b)²

To simplify the expression (0,5a-b)², we can use the formula for the square of a binomial.

The formula for the square of a binomial is: (a - b)² = a² - 2ab + b²

In this case, our binomial is (0,5a - b).

So, plugging this into the formula, we get: (0,5a - b)² = (0,5a)² - 2(0,5a)(b) + b²

Simplifying further, (0,5a - b)² = (0,25a²) - (ab) + b²

Therefore, (0,5a - b)² simplifies to (0,25a²) - (ab) + b².