令a=x-1/x则a²=x²-2+1/x²x²+1/x²=a²+2所以f(a)=a²+2所以f(x)=x²+2
姑孺驳驴800-200=600傅则现哼还困驴600傅姑困驳弄3擒疥笆现哼驳困600∴(3-1)=300傅300-200=100批¨给姑驳称100傅
