I'm trying to write a calculated question with multichoice options:

Calculate the following product $$(x+{={a}})(x+{={b}})$$

The problem is when writing the options, I just cant write the power, tried

$$pow(x,2)+{={a}+{b}}x+{={a}*{b}}$$

$$x^2+{={a}+{b}}x+{={a}*{b}}$$

$$x**2+{={a}+{b}}x+{={a}*{b}}$$

$$pow({x},2)+{={a}+{b}}x+{={a}*{b}}$$

All four return the same, for example the first one returns $$pow(x,2)+{={a}+{b}}x+{={a}*{b}}$$.

The values of a and b works fine