Let f(x)=1−cos(x−2)x.Select the correct description of the one-sided limits of f at x=2.Choose 1 answer:(A) limx→2+f(x)=+∞ and limx→2−f(x)=+∞(B) limx→2+f(x)=+∞ and limx→2−f(x)=−∞(C) limx→2+f(x)=−∞ and limx→2−f(x)=+∞(D) limx→2+f(x)=−∞ and limx→2−f(x)=−∞
Q. Let f(x)=1−cos(x−2)x.Select the correct description of the one-sided limits of f at x=2.Choose 1 answer:(A) limx→2+f(x)=+∞ and limx→2−f(x)=+∞(B) limx→2+f(x)=+∞ and limx→2−f(x)=−∞(C) limx→2+f(x)=−∞ and limx→2−f(x)=+∞(D) limx→2+f(x)=−∞ and limx→2−f(x)=−∞
Analyze Function Behavior: Analyze the function near the point of interest.We are interested in the behavior of the function f(x)=1−cos(x−2)x as x approaches 2. Specifically, we want to know the one-sided limits as x approaches 2 from the left (x→2−) and from the right (x→2+).
Consider Denominator Behavior: Consider the behavior of the denominator as x approaches 2. The denominator of f(x) is 1−cos(x−2). As x approaches 2, x−2 approaches 0. The cosine of 0 is 1, so the denominator approaches 20. We need to determine the sign of the denominator as x approaches 2 from the left and right to understand the behavior of f(x).
Sign of Denominator (Left): Determine the sign of the denominator as x approaches 2 from the left.As x approaches 2 from the left (x→2−), x−2 is slightly negative. The cosine function is even, so cos(x−2) is the same as cos(2−x). Since 2−x is slightly positive when x is just less than 2, and the cosine function is decreasing in the interval 21, cos(2−x) will be slightly less than 23. Therefore, 24 will be slightly positive, and the denominator will approach 25 from the positive side. This means that 26 will approach positive infinity.
Sign of Denominator (Right): Determine the sign of the denominator as x approaches 2 from the right.As x approaches 2 from the right (x→2(+)), x−2 is slightly positive. Since the cosine function is even, cos(x−2) will be slightly less than 1 for the same reasons as in Step 3. Therefore, 1−cos(x−2) will be slightly positive, and the denominator will approach 0 from the positive side. This means that 20 will approach positive infinity.
Combine Results: Combine the results from Steps 3 and 4 to answer the question.As x approaches 2 from both the left and the right, the denominator of f(x) approaches 0 from the positive side, causing f(x) to approach positive infinity in both cases. Therefore, the correct description of the one-sided limits of f at x=2 is:limx→2+f(x)=+∞ and limx→2−f(x)=+∞.
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