first off I would say don't house them together. One is bigger than the other though not hugely different but enough of one that the male (assuming the male is the larger of the two) can intimidate the female enough to keep her from eating etc. Also, age can mean a big thing. If the female is under 14 months old, she should not be with the male at all for any length of time (even 2 minutes is more than enough for the male to mate her).
I don't know if you bought them from the same source but both should be quarenteed to ensure neither picked up or have any sort of disease or parasites that can be transferred to the other. So, about 3 month quarentee would be needed, both in separate cages till you get 3 clean fecals done (each about a month apart). ALso, being separate, alot easer to know who poos regularly, who eats regularly, how much etc.
If both are of breeding age they will breed and you shouldn't let any animal breed till it is old enough (14 minimum for the female, 18 months or more is more highly recommmended) and if you are completely prepared and have homes for all the babies that will result from a single mating. A healthy female dragon can lay as anywhere between 3-6 clutches in one year, each clutch having between 10-30 eggs with 20 average. Thats a potential of 80 eggs or more with as many babies to care for and find homes for. Baby bearded dragons eat alot and I m ean, ALOT! 20 baby dragons can go through 3000 crickets a week easily.
It is alot better to house both separately, and if you do decide to breed and are fully prepared for the cost (food, housing, vet checks, advertising, suppliments, UVB bulbs etc) then you can introduce the male and female (when the female is old enough) to breed then separate them again.