Answer
False
Correct Statement:
$(x+y)^{-1} = \dfrac{1}{x+y}$
Work Step by Step
RECALL:
$a^{-m} = \dfrac{1}{a^m}$
Use the rule above to obtain:
$(x+y)^{-1} = \dfrac{1}{(x+y)^1}=\dfrac{1}{x+y}$
Thus, the given statement is false.
The correct statement is:
$(x+y)^{-1} = \dfrac{1}{x+y}$