Treat '$i$' just like a variable (like '$x$') during addition and subtraction. Only when performing multiplication do you need to apply the property $i^2 = -1$.
Step 1: Group the Real Parts: The real parts are $-1$ and $\frac{1}{2}$:
$$\text{Real Part} = -1 + \frac{1}{2}$$
$$\text{Real Part} = -\frac{2}{2} + \frac{1}{2} = -\frac{1}{2}$$
Step 2: Group the Imaginary Parts: The imaginary parts are $2i$ and $-i$:
$$\text{Imaginary Part} = 2i - i$$
$$\text{Imaginary Part} = (2 - 1)i = 1i = i$$
Step 3: Combine Results: Combining the simplified parts into the standard form $a + bi$:
$$\text{Result} = -\frac{1}{2} + i$$