$$\triangleq $$
≜\triangleq ≜
“组合版”:
\widetilde f \overset{\bigtriangleup}{=}
f~=△ \widetilde f \overset{\bigtriangleup}{=}f=△
$$\triangleq $$
≜\triangleq ≜
“组合版”:
\widetilde f \overset{\bigtriangleup}{=}
f~=△ \widetilde f \overset{\bigtriangleup}{=}f=△