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Evaluate the following limits : lim(n ...

Evaluate the following limits :
`lim_(n to 2)(n^(3)-8)/(n^(2)-4)`

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To evaluate the limit \( \lim_{n \to 2} \frac{n^3 - 8}{n^2 - 4} \), we can follow these steps: ### Step 1: Identify the form of the limit First, substitute \( n = 2 \) into the expression: \[ \frac{2^3 - 8}{2^2 - 4} = \frac{8 - 8}{4 - 4} = \frac{0}{0} \] This indicates that we have an indeterminate form \( \frac{0}{0} \). **Hint:** When you encounter \( \frac{0}{0} \), consider factoring the numerator and denominator. ### Step 2: Factor the numerator and denominator The numerator \( n^3 - 8 \) can be factored as a difference of cubes: \[ n^3 - 8 = n^3 - 2^3 = (n - 2)(n^2 + 2n + 4) \] The denominator \( n^2 - 4 \) can be factored as a difference of squares: \[ n^2 - 4 = n^2 - 2^2 = (n - 2)(n + 2) \] ### Step 3: Rewrite the limit with factored forms Now, substitute the factored forms back into the limit: \[ \lim_{n \to 2} \frac{(n - 2)(n^2 + 2n + 4)}{(n - 2)(n + 2)} \] **Hint:** Look for common factors in the numerator and denominator that can be canceled. ### Step 4: Cancel the common factors We can cancel the \( (n - 2) \) terms from the numerator and denominator: \[ \lim_{n \to 2} \frac{n^2 + 2n + 4}{n + 2} \] ### Step 5: Substitute \( n = 2 \) again Now substitute \( n = 2 \) into the simplified expression: \[ \frac{2^2 + 2 \cdot 2 + 4}{2 + 2} = \frac{4 + 4 + 4}{4} = \frac{12}{4} = 3 \] ### Final Answer Thus, the limit is: \[ \lim_{n \to 2} \frac{n^3 - 8}{n^2 - 4} = 3 \] ---
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MODERN PUBLICATION-LIMITS AND DERIVATIVES-EXERCISE 13 (a)
  1. Evaluate following limits : lim( x to -1)(x^(2)-1)/(x+1)

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  2. Evaluate the following limits : lim(x to 1)(x^(3)-1)/(x-1)

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  3. Evaluate the following limits : lim(n to 2)(n^(3)-8)/(n^(2)-4)

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  4. Evaluate the following limits : lim(x to 2)(x^(3)-2x^(2))/(x^(2)-5x+...

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  5. Find the value of the limit given below lim(n to 1/2)(4n^(2)-1)/(2n-1...

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  6. Evaluate the following limits : lim(x to 5)(x^(2)-9x+20)/(x^(2)-6x+5...

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  7. Evaluate the following limits : lim(x to 1)[(x-2)/(x^(2)-x)-1/(x^(3)...

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  8. Evaluate the following limits : lim(x to -1)(x^(3)+1)/(x+1).

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  9. If (lim)(x->-a)(x^9+a^9)/(x+a)9,\ find the real value of adot

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  10. Evaluate the left-hand and right-hand limits of the following function...

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  11. Find 'k' so that : lim(x to 2) f(x) exists, where : f(x)={{:(2x+3"...

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  12. Find 'k' so that : lim(x to 2) f(x) exists, where : f(x)={{:(2x+3"...

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  13. Find 'k' so that : lim(x to 2) f(x) exists, where : f(x)={{:(2x+3"...

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  14. Evaluate the following limits : lim(x to 1)(x^(15)-1)/(x^(10)-1)

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  15. Evaluate the following limits : lim(x to 0)((x+1)^(5)-1)/x

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  16. Prove that underset(xrarr0)"lim"((1+x)^(n) - 1)/(x) = n.

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  17. If ("lim")(xvec2)(x^n-2^n)/(x-2)=80a m dm in N ,t h e nfin dt h ev a ...

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  18. lim(x->3) {x^3-7x^2+15x-9}/{x^4-5x^3+27x-27} is equal to:

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  19. Evaluate: (lim)(x->sqrt(2))(x^9-3x^8+x^6-9x^4-4x^2-16 x+84)/(x^5-3x^4-...

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  20. Evaluate the following limits : lim(x to 0)(sqrt(1+x)-sqrt(1-x))/x

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