[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)= __

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

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

[题目]设 (x)=lim _(narrow infty )dfrac ((n-1)x)(n{x)^2+1} 则f(x)的间断点为 x=-|||-__ ..

1.设 (dfrac (1)(x))=x((dfrac {x)(x+1))}^2, 则 f(x)= ()-|||-(A) dfrac (1)(x)((dfrac

(3)设 (x)=dfrac (x)(sqrt {{x)^2+1}}, 则 f(f(x))= __ (2012计算机

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

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

设 (x+dfrac (1)(x))=(x)^2+dfrac (1)({x)^2}, 则 lim _(xarrow 3)f(x)= __

1.设 (x)=dfrac (1)(1-{x)^2}, 求 (-x),f[ f(x)] ,f[ dfrac (1)(f(x))]