Squeeze theorem applied to x^2 + x sin(1/x)
Consider the function for . Note that direct substitution fails at since is undefined there and oscillates wildly nearby. Use the fact that for all to construct upper and lower bounding functions for , and apply the Squeeze Theorem to evaluate State the value of this limit.
Hint
Start from , multiply through by (being careful this reverses inequalities when , but you can instead bound using ), then add to all sides and take the limit of the outer bounds.
Step-by-step solution
Since for all , multiplying by gives , which holds for both positive and negative . Adding to every part of this inequality yields , giving valid squeezing bounds near .
Now take the limit of the outer expressions as : both and approach by direct substitution, since these are continuous functions. Because is squeezed between two functions that both tend to , the Squeeze Theorem guarantees .
Behavior of the bounding functions near zero
Hint
Step-by-step solution
Both bounding functions, x squared minus the absolute value of x and x squared plus the absolute value of x, approach zero as x approaches zero. This shared value is exactly what forces the squeezed function g of x to also approach zero. The answer is zero.
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