148k views
2 votes
X+y=4 Convert the equation to polar coordinates and simplify.

User Leon Segal
by
7.3k points

1 Answer

4 votes

Final Answer:

In polar coordinates, the equation x + y = 4 simplifies to
\(r\cos(\theta) + r\sin(\theta) = 4.

Explanation:

Converting the Cartesian equation x + y = 4 into polar coordinates involves substituting
\(x = r\cos(\theta)\) and
\(y = r\sin(\theta)\). Starting with the original equation x + y = 4, we replace x and y with their respective polar coordinate forms to get
\(r\cos(\theta) + r\sin(\theta) = 4.

In this polar coordinate form, we can simplify by factoring out the common term r on the left side of the equation to obtain
\(r(\cos(\theta) + \sin(\theta)) = 4. This represents the equation in a more compact and manageable form.

The equation
\(r(\cos(\theta) + \sin(\theta)) = 4 can be interpreted geometrically as the sum of the projections of the point r onto the x and y axes, which collectively equals 4. It showcases a relationship between the distance of the point from the origin and the angles formed with the positive x axis.

Solving for r in terms of
\(\theta\) may involve further manipulation using trigonometric identities or expressing r explicitly to understand how the radius r changes with varying angles
\(\theta\) to fulfill the equation
\(r(\cos(\theta) + \sin(\theta))= 4. This transformation enables us to express the relationship between r and
\(\theta\) in polar coordinates for the given Cartesian equation.

The resulting equation in polar coordinates
\(r\cos(\theta) + r\sin(\theta) = 4 provides a concise representation of the relationship between the radius r and the angle
\(\theta\) in a polar system that satisfies the original Cartesian equation x + y = 4.

User Eliza Weisman
by
8.2k points