Start with your paper
Upload a PDF and select the sentence, equation, or proof step that stopped you.
An upload-first companion for formal mathematics
Upload a paper. Keep reading when one step stops you.
Add a PDF, select a sentence or equation, and get a focused explanation in plain language. Add Lean only when it helps you connect the idea to formal code.
Select a passage
It is enough to show that the target vector lies in the image of the linear map associated to the graph.
How it helps
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