Which of the following is a polar equation for the curve represented by the Cartesian equation ?
Table of contents
- 0. Review of College Algebra4h 45m
- 1. Measuring Angles40m
- 2. Trigonometric Functions on Right Triangles2h 5m
- 3. Unit Circle1h 19m
- 4. Graphing Trigonometric Functions1h 19m
- 5. Inverse Trigonometric Functions and Basic Trigonometric Equations1h 41m
- 6. Trigonometric Identities and More Equations2h 34m
- 7. Non-Right Triangles1h 38m
- 8. Vectors2h 25m
- 9. Polar Equations2h 5m
- 10. Parametric Equations1h 6m
- 11. Graphing Complex Numbers1h 7m
9. Polar Equations
Polar Coordinate System
Problem 7
Textbook Question
In Exercises 1–8, parametric equations and a value for the parameter t are given. Find the coordinates of the point on the plane curve described by the parametric equations corresponding to the given value of t. x = (60 cos 30°)t, y = 5 + (60 sin 30°)t − 16t²; t = 2
Verified step by step guidance1
Identify the parametric equations given: \(x = (60 \cos 30^\circ) t\) and \(y = 5 + (60 \sin 30^\circ) t - 16 t^2\).
Substitute the given value of the parameter \(t = 2\) into the equation for \(x\): calculate \(x = (60 \cos 30^\circ) \times 2\).
Substitute the same value \(t = 2\) into the equation for \(y\): calculate \(y = 5 + (60 \sin 30^\circ) \times 2 - 16 \times (2)^2\).
Recall the exact trigonometric values: \(\cos 30^\circ = \frac{\sqrt{3}}{2}\) and \(\sin 30^\circ = \frac{1}{2}\), and use these to simplify the expressions for \(x\) and \(y\).
After substituting and simplifying, write the coordinates of the point as \((x, y)\) corresponding to \(t = 2\).
Verified video answer for a similar problem:This video solution was recommended by our tutors as helpful for the problem above
Video duration:
5mPlay a video:
0 Comments
Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Parametric Equations
Parametric equations express the coordinates of points on a curve as functions of a parameter, often denoted as t. Instead of y as a function of x, both x and y depend on t, allowing the description of more complex curves and motions.
Recommended video:
Parameterizing Equations
Evaluating Trigonometric Functions at Specific Angles
Trigonometric functions like sine and cosine have known values at special angles such as 30°, 45°, and 60°. For example, cos 30° = √3/2 and sin 30° = 1/2. These values simplify calculations when substituting into parametric equations.
Recommended video:
Evaluate Composite Functions - Special Cases
Substitution and Calculation of Coordinates
To find the point on the curve for a given parameter t, substitute the value of t into the parametric equations for x and y. This involves arithmetic operations and applying trigonometric values to compute the exact coordinates of the point.
Recommended video:
Intro to Polar Coordinates
Related Videos
Related Practice
Multiple Choice
54
views
