[题目]已知 (dfrac (1)(x))=dfrac (5)(x)+2(x)^2, 则 f(x)=

[题目]设 (dfrac (1)(x))=dfrac (x)({x)^2+1} 则 f(x)=

[题目]设 (x+dfrac (1)(x))=(x)^2+dfrac (1)({x)^2}, 则f(x)= __

[题目]已知 (x+dfrac (1)(x))=dfrac ({x)^2}({x)^4+1}, 求f(x)

(1)已知 (x+dfrac (1)(x))=(x)^2+dfrac (1)({x)^2}, 则 f(x)= __ ;

【题文】已知：(x-dfrac (1)(x))=(x)^2+dfrac (1)({x)^2}-|||-__，则f(x)=________.【题文】已知：，则f(

7.已知函数 (x+dfrac (1)(x))=(x)^2+dfrac (1)({x)^2} ,则 f(x)=-|||-__

[题目]若 (dfrac (1)(x))=x, 则 (x)= ()-|||-A、 dfrac (1)(x)-|||-B、 dfrac (1)({x)^2}-||

已知 lim _(xarrow 0)([ 1+x+dfrac {f(x))(x)] }^dfrac (1{x)}=(e)^3, 则 lim _(xarrow 0

已知(x+dfrac (1)(x))=(x)^2+dfrac (1)({x)^2}-3，求f(x)已知，求f(x)

.已知 (dfrac (1)(x))=dfrac (4)(x)+2(x)^2+1, 求f(x), ((x)^2+1)