设lim_(x to 0) (sin 2x + xf(x))/(x^3) = 1，则lim_(x to 0) (2cos x + f(x))/(x^2) = (
3.计算下列极限(1) lim_(x→2)(-2) ;(2) lim_(x→1)(x^3-x^2+x-1) ;21(3)lim_(x→2)(x^2-16)/(x
3.计算下列极限(1) lim_(x→2)(-2) ;(2) lim_(x→1)(x^3-x^2+x-1) ;21(3)lim_(x→2)(x^2-16)/(x
8.设lim_(x to 0) (sin 2x + xf(x))/(x^3) = 1,则lim_(x to 0) (2cos x + f(x))/(x^2) =
例3 设f((x+1)/(x-1))=3f(x)-2x,求f(x).例3 设$f(\frac{x+1}{x-1})=3f(x)-2x$,求f(x).
设 lim_(xto-1)(x^3+ax^2+x+2)/(x+1)=b，则a=____，b=____. 第1空 第2空18. (4.0分) 设
5 设a,b为常数，且lim_(xtoinfty)(sqrt[3](1-x^6)-ax^2-b)=0，则a=____ b=____5 设a,b为常数，且$\li
(15)lim_(xtoinfty)((2x+3)/(2x+1))^x+1.(15)$\lim_{x\to\infty}\left(\frac{2x+3}{2x
11.已知lim_(x to 0) (ln(1+frac(f(x))/(x)))(2^x-1)=3，则lim_(x to 0) (f(x))/(sqrt(1+x
lim_(x arrow infty ) (2x^3-x+1)$ \lim_{x \rightarrow \infty } (2x^3-x+1) $