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Question

Question: $\lim_{x\to 1} \frac{x^{2024}-1}{x^{2022}-1}$...

limx1x20241x20221\lim_{x\to 1} \frac{x^{2024}-1}{x^{2022}-1}

Answer

10121011\frac{1012}{1011}

Explanation

Solution

The given limit is of the indeterminate form 00\frac{0}{0} as x1x \to 1. We can evaluate this limit using L'Hopital's Rule or by algebraic manipulation.

Method 1: L'Hopital's Rule

Applying L'Hopital's Rule, we differentiate the numerator and the denominator with respect to xx:

limx1x20241x20221=limx1ddx(x20241)ddx(x20221)=limx12024x20232022x2021\lim_{x\to 1} \frac{x^{2024}-1}{x^{2022}-1} = \lim_{x\to 1} \frac{\frac{d}{dx}(x^{2024}-1)}{\frac{d}{dx}(x^{2022}-1)} = \lim_{x\to 1} \frac{2024x^{2023}}{2022x^{2021}}

Now, substitute x=1x=1:

2024(1)20232022(1)2021=20242022=10121011\frac{2024(1)^{2023}}{2022(1)^{2021}} = \frac{2024}{2022} = \frac{1012}{1011}

Method 2: Algebraic Manipulation

We can factor the numerator and denominator using the difference of powers factorization: anbn=(ab)(an1+an2b++abn2+bn1)a^n - b^n = (a-b)(a^{n-1} + a^{n-2}b + \dots + ab^{n-2} + b^{n-1}).

x20241=(x1)(x2023+x2022++x+1)x^{2024}-1 = (x-1)(x^{2023} + x^{2022} + \dots + x + 1) x20221=(x1)(x2021+x2020++x+1)x^{2022}-1 = (x-1)(x^{2021} + x^{2020} + \dots + x + 1)

Substitute these factorizations into the limit expression:

limx1(x1)(x2023+x2022++x+1)(x1)(x2021+x2020++x+1)\lim_{x\to 1} \frac{(x-1)(x^{2023} + x^{2022} + \dots + x + 1)}{(x-1)(x^{2021} + x^{2020} + \dots + x + 1)}

Cancel the common factor (x1)(x-1) for x1x \neq 1:

limx1x2023+x2022++x+1x2021+x2020++x+1\lim_{x\to 1} \frac{x^{2023} + x^{2022} + \dots + x + 1}{x^{2021} + x^{2020} + \dots + x + 1}

Now, substitute x=1x=1 into the simplified expression. The numerator has 2024 terms, each equal to 1. The denominator has 2022 terms, each equal to 1.

20242022=10121011\frac{2024}{2022} = \frac{1012}{1011}

Thus, the limit is 10121011\frac{1012}{1011}.