Giới hạn của hàm số

A. $\underset{x\to +\infty }{\lim }f\left(x\right)=L$

B. $\underset{x\to -\infty }{\lim }f\left(x\right)=L$

C. $\underset{x\to x_0}{\lim }f\left(x\right)=L$

D. $\underset{x\to L}{\lim }f\left(x\right)=x_0$

A. $\frac{1}{5}$

B. $\sqrt{5}$

C. $\frac{1}{\sqrt{5}}$

D.5

A. $\underset{x\to x_0}{\lim }\left(f\left(x\right)+g\left(x\right)\right)=L$

B. $\underset{x\to x_0}{\lim }\left(f\left(x\right)+g\left(x\right)\right)=M$

C. $\underset{x\to x_0}{\lim }\left(f\left(x\right)+g\left(x\right)\right)=L-M$

D. $\underset{x\to x_0}{\lim }\left(f\left(x\right)+g\left(x\right)\right)=M+L$

A.0

B.1

C.2

D.3

A. $\underset{x\to x_0^{+}}{\lim }f\left(x\right)=L$

B. $\underset{x\to x_0^{-}}{\lim }f\left(x\right)=L$

C. $\underset{x\to +\infty }{\lim }f\left(x\right)=L$

D. $\underset{x\to -\infty }{\lim }f\left(x\right)=L$

A.1

B. $-\infty$

C.0

D. $+\infty$

A. $\underset{x\to x_0^{+}}{\lim }f\left(x\right)=L$

B. $\underset{x\to x_0^{+}}{\lim }f\left(x\right)=-L$

C. $\underset{x\to x_0^{-}}{\lim }f\left(x\right)=-L$

D. $\underset{x\to x_0^{+}}{\lim }f\left(x\right)=-\underset{x\to x_0^{-}}{\lim }f\left(x\right)$

A. $-\infty$

B. $+\infty$

C. $-\frac{15}{2}$

D.1

A. $\underset{x\to -\infty }{\lim }c=c$

B. $\underset{x\to +\infty }{\lim }\frac{c}{x^k}=+\infty$

C. $\underset{x\to -\infty }{\lim }{x}^k=0$

D. $\underset{x\to +\infty }{\lim }{x}^k=-\infty$

A. $\underset{x\to +\infty }{\lim }f\left(x\right)=+\infty \iff \underset{x\to +\infty }{\lim }\left(-f\left(x\right)\right)=+\infty$

B. $\underset{x\to +\infty }{\lim }f\left(x\right)=+\infty \iff \underset{x\to +\infty }{\lim }\left(-f\left(x\right)\right)=-\infty$

C. $\underset{x\to +\infty }{\lim }f\left(x\right)=+\infty \iff \underset{x\to -\infty }{\lim }\left(-f\left(x\right)\right)=-\infty$

D. $\underset{x\to +\infty }{\lim }f\left(x\right)=-\infty \iff \underset{x\to +\infty }{\lim }\left(-f\left(x\right)\right)=-\infty$

A.0

B. $+\infty$

C. $\sqrt{2}-1$

D. $-\infty$

A. $\underset{x\to +\infty }{\lim }{x}^n=-\infty$

B. $\underset{x\to \pm \infty }{\lim }{x}^n=+\infty$

C. $\underset{x\to -\infty }{\lim }{x}^n=-\infty$

D. $\underset{x\to -\infty }{\lim }{x}^n=+\infty$

A. $+\infty$

B.2

C.4

D. $-\infty$

A. $\underset{x\to +\infty }{\lim }\frac{x^2+1}{2x^2+1}=\frac{1}{2}$

B. $\underset{x\to -\infty }{\lim }\left(x^2+3x-1\right)=-\infty$

C. $\underset{x\to +\infty }{\lim }\frac{x+1}{2x+1}=\frac{1}{2}$

D. $\underset{x\to -\infty }{\lim }\frac{x+3}{2x+1}=\frac{1}{2}$