Precision of SQRT and POWER

Hello everybody,

following

DECLARE @arg AS DECIMAL(38, 19) = 25000000000000.000100

SELECT POWER(@arg, 0.5) AS power_result
,SQRT(@arg) AS sqrt_result

returns 5000000 though 5000000.00000000001 would be correct answer (and it is well inside the precision of the input parameter). The POWER-result would let one even assume that it is correct to the given precision, but it is not.

Are there any workarounds?