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Limit laws

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Intros
Lessons
  1. Limit Laws Overview:
    7 Properties of Limit Laws
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Examples
Lessons
  1. Evaluating Limits of Functions
    Evaluate the following limits using the property of limits:
    1. lim⁡x→2x2+4x+3\lim_{x \to 2} x^2+4x+3
    2. lim⁡x→23(x2+4x+3)2\lim_{x \to 2} 3(x^2+4x+3)^2
    3. lim⁡x→12−3x+4x22+x4\lim_{x \to 1} \frac{2-3x+4x^2}{2+x^4}
    4. lim⁡x→04(3)x\lim_{x \to 0} 4(3)^x
    5. lim⁡x→π23(sin⁡x)4\lim_{x \to \frac{\pi}{2}} 3(\sin x)^4
  2. Evaluating Limits with specific limits given
    Given that lim⁡x→5f(x)=−3\lim_{x \to 5} f(x)=-3, lim⁡x→5g(x)=5\lim_{x \to 5} g(x)=5, lim⁡x→5h(x)=2\lim_{x \to 5} h(x)=2, use the limit properties to compute the following limits:
    1. lim⁡x→5[5f(x)−2g(x)]\lim_{x \to 5} [5f(x)-2g(x)]
    2. lim⁡x→5[g(x)f(x)+3h(x)]\lim_{x \to 5} [g(x)f(x)+3h(x)]
    3. lim⁡x→52g(x)h(x)\lim_{x \to 5} \frac{2g(x)}{h(x)}
    4. lim⁡x→55[f(x)]3g(x)\lim_{x \to 5} \frac{5[f(x)]^3}{g(x)}
Topic Notes
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Here are some properties of limits:

1) lim⁡x→ax=a\lim_{x \to a} x = a
2) lim⁡x→ac=c\lim_{x \to a} c = c
3) lim⁡x→a[cf(x)]=clim⁡x→af(x)\lim_{x \to a} [cf(x)] = c\lim_{x \to a}f(x)
4) lim⁡x→a[f(x)±g(x)]=lim⁡x→af(x)±lim⁡x→ag(x)\lim_{x \to a} [f(x) \pm g(x)] = \lim_{x \to a}f(x) \pm \lim_{x \to a}g(x)
5) lim⁡x→a[f(x)g(x)]=lim⁡x→af(x)lim⁡x→ag(x)\lim_{x \to a} [f(x) g(x)] = \lim_{x \to a}f(x) \lim_{x \to a}g(x)
6) lim⁡x→af(x)g(x)=lim⁡x→af(x)lim⁡x→ag(x)\lim_{x \to a} \frac{f(x)}{g(x)} = \frac{\lim_{x \to a}f(x)}{\lim_{x \to a}g(x)}, only if lim⁡x→ag(x)≠0\lim_{x \to a}g(x) \neq0
7) lim⁡x→a[f(x)]n=[lim⁡x→af(x)]n\lim_{x \to a} [f(x)]^n=[\lim_{x \to a}f(x)]^n

Where c is a constant, lim⁡x→af(x)\lim_{x \to a} f(x) and lim⁡x→ag(x)\lim_{x \to a} g(x) exist.

Here is a fact that may be useful to you.
If P(x)P(x) is a polynomial, then
lim⁡x→aP(x)=P(a)\lim_{x \to a} P(x)=P(a)
Basic Concepts
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