Chapter 2: Problem 17
Determine the equation of the tangent line to the given path at the specified value of \(t.\) $$\left(\sin 3 t, \cos 3 t, 2 t^{5 / 2}\right) ; t=1$$
Short Answer
Expert verified
The tangent line is parameterized by: \( x = \sin(3) + 3t\cos(3), y = \cos(3) - 3t\sin(3), z = 2 + 5t \).
Step by step solution
01
Define the Parametric Equations
The given parametric equations are \( x = \sin(3t) \), \( y = \cos(3t) \), and \( z = 2t^{5/2} \). Identify these as the functions describing the path.
02
Find the Point at \(t = 1\)
Substitute \( t = 1 \) into the parametric equations to find the coordinates of the point. Thus, \( x(1) = \sin(3 \cdot 1) = \sin(3) \), \( y(1) = \cos(3 \cdot 1) = \cos(3) \), and \( z(1) = 2(1)^{5/2} = 2 \). Thus, the point is \((\sin(3), \cos(3), 2)\).
03
Find the Velocity Vector
Calculate the derivatives of the parametric equations with respect to \(t\) to get the components of the velocity vector.\[ \frac{dx}{dt} = 3\cos(3t) \], \[ \frac{dy}{dt} = -3\sin(3t) \], and \[ \frac{dz}{dt} = 5t^{3/2} \].
04
Evaluate the Velocity at \(t = 1\)
Substitute \( t = 1 \) into the derivatives to find the velocity vector at this instant.\[ \frac{dx}{dt}(1) = 3\cos(3) \], \[ \frac{dy}{dt}(1) = -3\sin(3) \], and \[ \frac{dz}{dt}(1) = 5(1)^{3/2} = 5 \]. The velocity vector is \((3\cos(3), -3\sin(3), 5)\).
05
Write the Equation of the Tangent Line
The equation of the tangent line is given by the point and the direction vector (velocity vector). Write the equation in parametric form: \( x = \sin(3) + 3t\cos(3) \), \( y = \cos(3) - 3t\sin(3) \), \( z = 2 + 5t \).
Unlock Step-by-Step Solutions & Ace Your Exams!
-
Full Textbook Solutions
Get detailed explanations and key concepts
-
Unlimited Al creation
Al flashcards, explanations, exams and more...
-
Ads-free access
To over 500 millions flashcards
-
Money-back guarantee
We refund you if you fail your exam.
Over 30 million students worldwide already upgrade their learning with 91Ó°ÊÓ!
Key Concepts
These are the key concepts you need to understand to accurately answer the question.
Parametric Equations
Parametric equations are a way of representing mathematical curves. Instead of expressing variables like x and y directly in terms of each other, each is expressed as a function of a third variable, usually t. This method is especially useful for plotting curves in multiple dimensions.
- In the given problem, the parametric equations are: \( x = \sin(3t) \), \( y = \cos(3t) \), and \( z = 2t^{5/2} \).
- Each equation describes how the x, y, and z positions change with t.
- Visualize it like plotting the path of an airplane flying through 3D space.
Velocity Vector
The velocity vector provides insight into the speed and direction of an object at a particular instance on its path. It is derived by taking the derivatives of the parametric equations with respect to the variable t.
- To find the velocity, calculate the derivatives: \( \frac{dx}{dt} = 3\cos(3t) \), \( \frac{dy}{dt} = -3\sin(3t) \), and \( \frac{dz}{dt} = 5t^{3/2} \).
- These derivatives reflect how fast and in which direction the parameters x, y, and z change as t changes.
Calculus
Calculus is an essential mathematical tool for understanding change and motion. It enables us to determine slopes, curvatures, and the behavior of functions.
Derivatives
Derivatives play a crucial role. They help find the rate at which a function is changing. By calculating the derivative, we acquire the slope of a curve or the rate of change at any given point.- The derivative of a position function gives the velocity, which we used earlier to find the velocity vector.
- This approach allows us to predict how an object moves along a curved path.
Tangent Lines
A tangent line represents the best linear approximation to a curve at a particular point.- By combining a point obtained from the parametric equations and the velocity vector, we define the tangent line.
- This line is instrumental when analyzing real-world problems like motion trajectories and assessing instantaneous changes.