What was the geometry student looking for at the beach

失落的我

Q: What was the geometry student looking for at the beach?
" l& c/ Z. m) |9 c* V5 _' \8 d) S
9 X- t* m# ^' S. w* EA: A tangent.

tangent  
- u) m$ n& W0 r7 o$ [% g: L) e' P  H/ P noun
$ p5 S: W; L) w2 R" @ (geometry) a straight line that touches the outside of a curve but does not cross it