Câu 9: C
Câu 12: D
Câu 13:
\(\lim\limits_{n\rightarrow+\infty}\left(u_n+v_n\right)=6+2=8\)
=>Chọn B
Câu 14:
\(\lim\limits_{x\rightarrow1^+}2x-5=2\cdot1-5=-3< 0\)
\(\lim\limits_{x\rightarrow1^+}x-1=1-1=0\)
=>\(\lim\limits_{x\rightarrow1^+}\dfrac{2x-5}{x-1}=-\infty\)
=>Chọn A
Câu 15:
\(\lim\limits_{x\rightarrow2}\left(2x^2+1\right)=2\cdot2^2+1=2\cdot4+1=9\)
=>Chọn B