We read your photo as:

Let f be defined by f(x)= 4−x2 & if x 1 2+x2 & if x > 1. Find each of the following limits if they exist: (i) x 1^- f(x) (ii) x 1^+ f(x) (iii) _x 1 f(x)

Mathematics

ScanSolve AI Answer

Graph of f(x) = 4 − x²

Use the left and right arrow keys to trace the curve, up and down to jump between key points, and plus and minus to zoom.

Key points of f(x) = 4 − x²
Pointxy
x-intercept−20
Maximum04
x-intercept20

Step-by-step solution

9 steps

Here are the points of discontinuity for each function:

Part a· 3 steps

For the function f(x)={x2+x−6x+3if x≠−3−5if x=−3f(x) = \begin{cases} \frac{x^2+x-6}{x+3} & \text{if } x \neq -3 \\ -5 & \text{if } x = -3 \end{cases}

  1. Check the function value at x=−3x=-3.

    f(−3)=−5f(-3) = -5

    The function is defined at x=−3x=-3.

  2. Evaluate the limit as x→−3x \to -3.

    For x≠−3x \neq -3, we can simplify the expression:

    x2+x−6x+3=(x+3)(x−2)x+3=x−2\frac{x^2+x-6}{x+3} = \frac{(x+3)(x-2)}{x+3} = x-2

    Now, find the limit:

    lim⁡x→−3f(x)=lim⁡x→−3(x−2)=−3−2=−5\lim_{x \to -3} f(x) = \lim_{x \to -3} (x-2) = -3-2 = -5

    The limit exists.

  3. Compare the function value and the limit.

    Since lim⁡x→−3f(x)=−5\lim_{x \to -3} f(x) = -5 and f(−3)=−5f(-3) = -5, we have lim⁡x→−3f(x)=f(−3)\lim_{x \to -3} f(x) = f(-3).
    For all other values of xx, the function is a polynomial (after simplification), which is continuous.
    Therefore, the function f(x)f(x) is continuous everywhere.
    There are no values of xx for which f(x)f(x) is not continuous.

Part b· 3 steps

For the function h(x)={x2+x−6x+3if x≠−31if x=−3h(x) = \begin{cases} \frac{x^2+x-6}{x+3} & \text{if } x \neq -3 \\ 1 & \text{if } x = -3 \end{cases}

  1. Check the function value at x=−3x=-3.

    h(−3)=1h(-3) = 1

    The function is defined at x=−3x=-3.

  2. Evaluate the limit as x→−3x \to -3.

    As shown in part (a), for x≠−3x \neq -3, x2+x−6x+3=x−2\frac{x^2+x-6}{x+3} = x-2.

    lim⁡x→−3h(x)=lim⁡x→−3(x−2)=−3−2=−5\lim_{x \to -3} h(x) = \lim_{x \to -3} (x-2) = -3-2 = -5

    The limit exists.

  3. Compare the function value and the limit.

    Since lim⁡x→−3h(x)=−5\lim_{x \to -3} h(x) = -5 and h(−3)=1h(-3) = 1, we have lim⁡x→−3h(x)≠h(−3)\lim_{x \to -3} h(x) \neq h(-3).
    Therefore, the function h(x)h(x) is not continuous at ∗x=−3∗\boxed*{x=-3}* because the limit of the function as xx approaches −3-3 does not equal the function's value at x=−3x=-3.

Part c· 2 steps

For the function g(x)={1x+3if x≠−33if x=−3g(x) = \begin{cases} \frac{1}{x+3} & \text{if } x \neq -3 \\ 3 & \text{if } x = -3 \end{cases}

  1. Check the function value at x=−3x=-3.

    g(−3)=3g(-3) = 3

    The function is defined at x=−3x=-3.

  2. Evaluate the limit as x→−3x \to -3.

    Consider the one-sided limits:

    lim⁡x→−3+1x+3=+∞\lim_{x \to -3^+} \frac{1}{x+3} = +\infty lim⁡x→−3−1x+3=−∞\lim_{x \to -3^-} \frac{1}{x+3} = -\infty

    Since the left-hand limit and the right-hand limit are not equal (and both are infinite), the limit lim⁡x→−3g(x)\lim_{x \to -3} g(x) does not exist.
    Therefore, the function g(x)g(x) is not continuous at ∗x=−3∗\boxed*{x=-3}* because the limit of the function as xx approaches −3-3 does not exist.

Part d· 1 step

For the function f(x)=∣x∣xf(x) = \frac{|x|}{x}

  1. Check the function value at x=0x=0.

    The expression ∣x∣x\frac{|x|}{x} involves division by xx. If x=0x=0, the denominator is zero.

    f(0)=∣0∣0=00f(0) = \frac{|0|}{0} = \frac{0}{0}

    The function f(x)f(x) is undefined at x=0x=0.
    Therefore, the function f(x)f(x) is not continuous at ∗x=0∗\boxed*{x=0}* because the function is undefined at this point.

Was this helpful?

Still stuck on this one?

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

Got a different question?Ask your own question