Question

Plot each point in polar coordinates. $$\left(4,35^{\circ}\right)$$

Short answer

To plot \((4,35^\circ)\) in polar coordinates, draw a line at a 35-degree angle to the x-axis and measure 4 units along this line to locate the point.

Step-by-step solution

Understand Polar Coordinates

Polar coordinates represent a point in a two-dimensional plane with a radius (r) and an angle (θ) relative to the positive x-axis. The radius indicates how far from the origin the point is, and the angle indicates the direction from the origin to the point.

Plot the point

To plot the point \((4,35^\circ)\), first draw a line at an angle of 35 degrees to the positive x-axis starting from the origin. Then, measure a distance of 4 units along this line away from the origin. Mark the point at this location.

Key concepts

Plotting Polar Coordinates

Understanding how to plot points using polar coordinates is essential in various fields such as physics, engineering, and mathematics. Unlike the Cartesian coordinate system, which uses a grid of vertical and horizontal lines, polar coordinates express the location of a point as a distance and direction from a central point, called the origin. To plot a point like \( (4,35^\circ) \), you start by facing the positive x-axis and rotating counterclockwise to the given angle, here 35 degrees. This sets the direction. Next, you walk outwards from the origin the number of steps corresponding to the radius—in this case, 4 units. Mark the point where you stop. This simple method allows for a quick visualization on a two-dimensional plane without the need for a grid.

Radius and Angle

In polar coordinates, the radius and angle are the two critical pieces of information that define a point's location. The radius, often denoted as \( r \), is a line segment from the origin to the point. It tells us how far the point is from the center of the coordinate system. The angle, designated as \( \theta \), is measured in degrees or radians and shows the counterclockwise rotation from the positive x-axis to the line segment representing the radius. Combining the radius and angle provides us with a complete picture of where a point is situated. For example, a point with coordinates \( (4,35^\circ) \), has a radius of 4 units from the origin and is located 35 degrees above the positive x-axis.

Polar Coordinate System

The polar coordinate system is an alternative to the Cartesian system for representing points on a two-dimensional plane. It's particularly useful in scenarios where points form circular or spiral patterns. In this system, each point is determined by the radius \( r \), which can be any non-negative real number, and the angle \( \theta \), which can range from 0 to 360 degrees (or from 0 to \( 2\pi \) radians). One of the beauties of this system is its ability to simplify equations and calculations for curves like circles and spirals. It also reminds us that positions can be relative; a point can be described differently depending on the chosen frame of reference or coordinate system.

Two-Dimensional Plane

A two-dimensional plane is a flat surface that extends infinitely in all directions within its dimension. It's the cornerstone for plotting both Cartesian and polar coordinates. When dealing with polar coordinates, we visualize the plane as having a central point, which we refer to as the origin, or pole, and a baseline, known as the polar axis, which corresponds to the 0-degree direction for measuring angles, typically identical to the positive x-axis in Cartesian coordinates. All points are described in relation to these references. While this might seem abstract, imagining a two-dimensional plane is as simple as picturing a vast sheet of paper with the origin as a small dot right at its center. For polar coordinates, think of this dot as your starting point for every plotted point.