/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 41 Evaluate the following limits. ... [FREE SOLUTION] | 91Ó°ÊÓ

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Evaluate the following limits. $$\lim _{t \rightarrow \pi / 2}\left(\cos 2 t \mathbf{i}-4 \sin t \mathbf{j}+\frac{2 t}{\pi} \mathbf{k}\right)$$

Short Answer

Expert verified
$$ Answer: As t approaches π/2, the limit of the vector-valued function is: $$(-1\mathbf{i} - 4\mathbf{j} + 1\mathbf{k})$$

Step by step solution

01

Evaluate the limit for the i-component

The i-component of the given vector function is cos(2t). To find its limit as t approaches π/2, simply substitute π/2 into the function: $$\lim_{t \rightarrow \pi/2} \cos(2t) = \cos(2(\pi/2)) = \cos(\pi)$$ Since cos(π) = -1, the limit for the i-component is: $$\lim_{t \rightarrow \pi/2}\cos(2t) \mathbf{i} = -1\mathbf{i}$$
02

Evaluate the limit for the j-component

The j-component of the given vector function is -4sin(t). To find its limit as t approaches π/2, substitute π/2 into the function: $$\lim_{t \rightarrow \pi/2} -4\sin(t) = -4\sin(\pi/2)$$ Since sin(π/2) = 1, the limit for the j-component is: $$\lim_{t \rightarrow \pi/2} -4\sin(t) \mathbf{j} = -4\mathbf{j}$$
03

Evaluate the limit for the k-component

The k-component of the given vector function is (2t/π). To find its limit as t approaches π/2, substitute π/2 into the function: $$\lim_{t \rightarrow \pi/2} \frac{2t}{\pi} = \frac{2(\pi/2)}{\pi}$$ Simplifying the expression, we get: $$\lim_{t \rightarrow \pi/2} \frac{2t}{\pi} \mathbf{k} =1\mathbf{k}$$
04

Combine the components

Now that we have evaluated the limit for each component, we can combine them to obtain the limit of the entire vector-valued function: $$\lim_{t \rightarrow \pi/2} \left(\cos(2t) \mathbf{i} - 4\sin(t) \mathbf{j} + \frac{2t}{\pi} \mathbf{k}\right) = (-1\mathbf{i} - 4\mathbf{j} + 1\mathbf{k})$$

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Most popular questions from this chapter

Evaluate the following limits. $$\lim _{t \rightarrow 0}\left(\frac{\sin t}{t} \mathbf{i}-\frac{e^{t}-t-1}{t} \mathbf{j}+\frac{\cos t+t^{2} / 2-1}{t^{2}} \mathbf{k}\right)$$

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The function \(f(x)=\sin n x,\) where \(n\) is a positive real number, has a local maximum at \(x=\pi /(2 n)\) Compute the curvature \(\kappa\) of \(f\) at this point. How does \(\kappa\) vary (if at all) as \(n\) varies?

Note that two lines \(y=m x+b\) and \(y=n x+c\) are orthogonal provided \(m n=-1\) (the slopes are negative reciprocals of each other). Prove that the condition \(m n=-1\) is equivalent to the orthogonality condition \(\mathbf{u} \cdot \mathbf{v}=0\) where \(\mathbf{u}\) points in the direction of one line and \(\mathbf{v}\) points in the direction of the other line.

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