We read your photo as:

Evaluate the ff limits, if they exist (i) lim x->1 (x8 - 1)/(x10 - 1) (ii) lim x->3 (x2 - 9)/(x2 + 2x - 3)

Mathematics

ScanSolve AI Answer

Answers

2 parts
i

45\frac{4}{5}

ii

32\frac{3}{2}

Step-by-step solution

7 steps

Here are the evaluations of the limits.

Part i· 3 steps

Evaluate lim⁡x→1x8−1x10−1\lim_{x \to 1} \frac{x^8 - 1}{x^{10} - 1}

  1. Check the form of the limit.

    If we substitute x=1x=1 into the expression, we get 18−1110−1=00\frac{1^8 - 1}{1^{10} - 1} = \frac{0}{0}, which is an indeterminate form. This means we can apply L'Hôpital's Rule.

  2. Apply L'Hôpital's Rule.

    Take the derivative of the numerator and the derivative of the denominator with respect to xx.
    Derivative of the numerator: ddx(x8−1)=8x7\frac{d}{dx}(x^8 - 1) = 8x^7
    Derivative of the denominator: ddx(x10−1)=10x9\frac{d}{dx}(x^{10} - 1) = 10x^9

  3. Evaluate the limit of the new expression.

    lim⁡x→18x710x9\lim_{x \to 1} \frac{8x^7}{10x^9}

    Substitute x=1x=1:

    8(1)710(1)9=810=45\frac{8(1)^7}{10(1)^9} = \frac{8}{10} = \frac{4}{5}

    The limit exists and is:

    45\boxed{\frac{4}{5}}

Part ii

32\frac{3}{2}

Evaluate lim⁡x→−3x2−9x2+2x−3\lim_{x \to -3} \frac{x^2 - 9}{x^2 + 2x - 3}

  1. Check the form of the limit.

    If we substitute x=−3x=-3 into the expression, we get (−3)2−9(−3)2+2(−3)−3=9−99−6−3=00\frac{(-3)^2 - 9}{(-3)^2 + 2(-3) - 3} = \frac{9 - 9}{9 - 6 - 3} = \frac{0}{0}, which is an indeterminate form. We can apply L'Hôpital's Rule or factor the expression. Let's use factoring for this one.

  2. Factor the numerator and the denominator.

    Numerator: x2−9=(x−3)(x+3)x^2 - 9 = (x-3)(x+3)
    Denominator: x2+2x−3=(x+3)(x−1)x^2 + 2x - 3 = (x+3)(x-1)

  3. Substitute the factored expressions back into the limit and simplify.

    lim⁡x→−3(x−3)(x+3)(x+3)(x−1)\lim_{x \to -3} \frac{(x-3)(x+3)}{(x+3)(x-1)}

    Since x→−3x \to -3, x≠−3x \neq -3, so we can cancel the (x+3)(x+3) term.

    lim⁡x→−3x−3x−1\lim_{x \to -3} \frac{x-3}{x-1}
  4. Evaluate the limit by direct substitution.

    Substitute x=−3x=-3:

    −3−3−3−1=−6−4=32\frac{-3-3}{-3-1} = \frac{-6}{-4} = \frac{3}{2}

    The limit exists and is:

    32\boxed{\frac{3}{2}}
Was this helpful?

Try one yourself

A new problem that tests the same skill.

Still stuck on this one?

Ask a follow-up, and the answer starts from this question.

Got a different question?Ask your own question
Handwritten step-by-step solution preview

Handwritten Step-by-Step Solution

Get this as a handwritten image on WhatsApp — like a tutor wrote it for you.

Try on WhatsApp