(0,3x-0,5a)²

To simplify the expression \((0.3x - 0.5a)^2\), we can use the binomial squaring formula, which states:

\[ (a - b)^2 = a^2 - 2ab + b^2 \]

In this case, let \( a = 0.3x \) and \( b = 0.5a \). Now we apply the formula:

\[ (0.3x - 0.5a)^2 = (0.3x)^2 - 2(0.3x)(0.5a) + (0.5a)^2 \]

Now we calculate each term:

1. \((0.3x)^2 = 0.09x^2\)
2. \(-2(0.3x)(0.5a) = -0.3x \cdot a = -0.3ax\)
3. \((0.5a)^2 = 0.25a^2\)

Putting it all together, we get:

\[ (0.3x - 0.5a)^2 = 0.09x^2 - 0.3ax + 0.25a^2 \]

So, the simplified expression is:

\[ 0.09x^2 - 0.3ax + 0.25a^2 \]