Because God creates. Man doesn't "create". Man uses to "create" what God already gave to us for a resource. Calculus is just a measuring tool - it is not an explanation of how the earth started or life.
But this doesn't answer mlc9852's question as to why other scientific theories don't raise objections concerning God. What about meteorology, for example. The Bible specifically says, in the book of Amos, that "God creates the wind." The verb is a form of the same used in Genesis, which creationist fundamentalists sometimes insist only refers to creation ex nihilo.
If God "creates" the wind, why (by your own professed standards) is it not a denial of God to claim that wind is created by thermodynamically formed convection cells and other such strictly naturalistic mechanisms?
Not so...
Jesus came to make ALL religion obsolete, AND DID...
Christianity, according to Jesus, is a family, not a tax exempt organization..
Christianity NOT according to Jesus can be anything and CAN be a tax exempt organization..
i.e. not all christians are christians and not Evos are atheists..
On the contrary, I've created many things. Including these posts, for example. God didn't deliver them into my email box and ask me to forward them for him.
But if you feel that God is the ultimate author of my posts after all, perhaps you should pay them more heed.