Answer:
[tex]8[/tex]
Step-by-step explanation:
Note that 1/2 xy^2 is, by order of operations, read as [tex]\frac12xy^2[/tex]. If this is not what was intended in the question then please amend it according order of operations.
Plugging the values [tex]x=4[/tex] and [tex]y=-2[/tex] gives
[tex]\frac12xy^2=\frac12(4)(-2)^2=\frac12(4)(4)=\frac12(16)=8[/tex]
