+) TH1: m=nChia x^n:
f(x)=\frac{\frac{a_nx^n}{x^n}+\frac{a_{n-1}x^{n-1}}{x^n}+......+\frac{a_1x}{x^n}+\frac{a_0}{x^n}}{\frac{b_nx^n}{x^n}+........................+\frac{b_0}{x^n}}
=> \mathop {\lim }\limits_{x \to +\infty }f(x)=\mathop {\lim }\limits_{x \to +\infty }\frac{an}{bn}=\frac{a}{b}.
+) TH2: m>n
Chia x^m:
f(x)=\frac{\frac{a_nx^n}{x^m}+.................+\frac{a_0}{x^m}}{\frac{b_mx^m}{x^m}+..............\frac{b_0}{x^m}}
=>\mathop {\lim }\limits_{x \to +\infty }f(x)=\mathop {\lim }\limits_{x \to +\infty }\frac{0}{b_m}=0
+) TH3: m<n không có đường tiệm cận =>\varnothing
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TQ:
\mathop {\lim }\limits_{x \to \pm \infty }f(x)=\frac{an}{bm}.\mathop {\lim }\limits_{x \to \pm \infty }x^{n-m}
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3TF, mãi mãi một tình yêu <3