int_(1)^sqrt(3) dfrac(d x)(x^2 sqrt(1+x^2))

int dfrac (1)({x)^2}sqrt (dfrac {1-x)(1+x)}dx

A.sqrt(1+x) B.(sqrt(1+x))/(2) C.(sqrt(1+x))/(sqrt(x)) D.(sqrt(1+x))/(2sqrt(x)

[题目] lim _(xarrow 1)dfrac (sqrt {3-x)-sqrt (1+x)}({x)^2+x-2}= __

2.lim _(xarrow 1)dfrac (sqrt {3-x)-sqrt (1+x)}({x)^2+x-2}=2.

lim _(xarrow 1)dfrac (sqrt {3-x)-sqrt (1+x)}({x)^2-1}-|||-__

求：int dfrac (arctan sqrt {x)}(sqrt {x)(1+x)}dx求：

计算int dfrac (arctan sqrt {x)}(sqrt {x)(1+x)}dx计算

=dfrac (sqrt {1+x)-sqrt (1-x)}(sqrt {1+x)+sqrt (1-x)}

lim _(xarrow 0)dfrac (sqrt {1+x)+sqrt (1-x)-2}(sqrt {1+{x)^2}-1}

int dfrac (dx)(sqrt {x(1+x))}