"this is obvious from" is correct and can be used in written English.
It is used to introduce evidence or a justification for something. For example, "This is obvious from the increasing number of people who are getting vaccinated."
This is obvious from the sketch of the field lines of this configuration below.
In south London this is obvious from the profusion of pentecostal churches, mostly nowadays west African.
This is obvious from the fact that we safely deal with these wastes from our present nuclear power plants.
"Neither side can defeat the other militarily, this is obvious from more than three months of fighting," he said.
This is obvious from the conversations that are held there, notably those delayed until the door clicks shut.
The arbitrariness of all this is obvious from the fact that among surfers there is no such thing as a nine-foot wave or a thirteen-foot wave.
(b) But if it is really intermediate, in this way too there would have to be a change to white, which was not from not-white; but as it is, this is never seen.-Again, every object of understanding or reason the understanding either affirms or denies-this is obvious from the definition-whenever it says what is true or false.
This is obvious for T1 from the observation that {T1 > t} = {N t) = 0}.
"I'd always hoped this was obvious from it being quite good, but apparently clarification would help".
Meyer says he thought this was obvious from the tone of Bush's State of the Union address in 2003.
This was obvious from the questions they asked me during the discussions and the topics they discussed about amongst themselves when I divided them in groups.
