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Determine whether the function 
f(x) is continuous at 
x=3.

f(x)={[7-2x^(2)",",x <= 3],[-8-x",",x > 3]:}

f(x) is continuous at 
x=3
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f(x) is discontinuous at 
x=3

Determine whether the function f(x) f(x) is continuous at x=3 x=3 .\newlinef(x)={72x2,amp;x38x,amp;xgt;3 f(x)=\left\{\begin{array}{ll} 7-2 x^{2}, &amp; x \leq 3 \\ -8-x, &amp; x&gt;3 \end{array}\right. \newlinef(x) f(x) is continuous at x=3 x=3 \newlineSubmit Answer\newlinef(x) f(x) is discontinuous at x=3 x=3

Full solution

Q. Determine whether the function f(x) f(x) is continuous at x=3 x=3 .\newlinef(x)={72x2,x38x,x>3 f(x)=\left\{\begin{array}{ll} 7-2 x^{2}, & x \leq 3 \\ -8-x, & x>3 \end{array}\right. \newlinef(x) f(x) is continuous at x=3 x=3 \newlineSubmit Answer\newlinef(x) f(x) is discontinuous at x=3 x=3
  1. Check Function Definition: To determine if the function f(x)f(x) is continuous at x=3x=3, we need to check three conditions:\newline11. The function is defined at x=3x=3.\newline22. The limit of f(x)f(x) as xx approaches 33 from the left is equal to the limit of f(x)f(x) as xx approaches 33 from the right.\newline33. The limit of f(x)f(x) as xx approaches 33 is equal to the function value at x=3x=3.
  2. Find Left Limit: First, let's check if the function is defined at x=3x=3. We have two expressions for f(x)f(x), one for x3x \leq 3 and one for x > 3. Since 33 is included in the domain of the first expression, we will use that to find f(3)f(3).
    f(3)=72(3)2f(3) = 7 - 2(3)^2
    f(3)=72(9)f(3) = 7 - 2(9)
    f(3)=718f(3) = 7 - 18
    f(3)=11f(3) = -11
    The function is defined at x=3x=3 and f(3)=11f(3) = -11.
  3. Find Right Limit: Next, we need to find the limit of f(x)f(x) as xx approaches 33 from the left. This means we will use the expression for f(x)f(x) when x3x \leq 3.\newlinelimx3f(x)=limx3(72x2)\lim_{x\to 3^-} f(x) = \lim_{x\to 3^-} (7 - 2x^2)\newlinelimx3f(x)=72(3)2\lim_{x\to 3^-} f(x) = 7 - 2(3)^2\newlinelimx3f(x)=718\lim_{x\to 3^-} f(x) = 7 - 18\newlinelimx3f(x)=11\lim_{x\to 3^-} f(x) = -11
  4. Verify Continuity: Now, we need to find the limit of f(x)f(x) as xx approaches 33 from the right. This means we will use the expression for f(x)f(x) when x > 3.limx3+f(x)=limx3+(8x)\lim_{x\to 3^+} f(x) = \lim_{x\to 3^+} (-8 - x)limx3+f(x)=83\lim_{x\to 3^+} f(x) = -8 - 3limx3+f(x)=11\lim_{x\to 3^+} f(x) = -11
  5. Verify Continuity: Now, we need to find the limit of f(x)f(x) as xx approaches 33 from the right. This means we will use the expression for f(x)f(x) when x > 3.limx3+f(x)=limx3+(8x)\lim_{x\to3+} f(x) = \lim_{x\to3+} (-8 - x)limx3+f(x)=83\lim_{x\to3+} f(x) = -8 - 3limx3+f(x)=11\lim_{x\to3+} f(x) = -11Since the limit from the left and the limit from the right both equal 11-11, and the function value at x=3x=3 is also 11-11, all three conditions for continuity are satisfied. Therefore, f(x)f(x) is continuous at x=3x=3.

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