Questions: Convert the following equation to polar coordinates.
y=8/x
(Type an expression using θ as the variable.)
Transcript text: Convert the following equation to polar coordinates.
\[
y=\frac{8}{x}
\]
(Type an expression using $\theta$ as the variable.)
Solution
Solution Steps
To convert the given equation \( y = \frac{8}{x} \) to polar coordinates, we need to use the relationships between Cartesian coordinates \((x, y)\) and polar coordinates \((r, \theta)\). Specifically, we use \( x = r \cos(\theta) \) and \( y = r \sin(\theta) \). Substitute these into the given equation and solve for \( r \).
Step 1: Convert Cartesian Coordinates to Polar Coordinates
Given the equation in Cartesian coordinates:
\[
y = \frac{8}{x}
\]
we use the relationships between Cartesian and polar coordinates:
\[
x = r \cos(\theta) \quad \text{and} \quad y = r \sin(\theta)
\]
Step 2: Substitute Polar Coordinates into the Equation
Substitute \( x = r \cos(\theta) \) and \( y = r \sin(\theta) \) into the given equation:
\[
r \sin(\theta) = \frac{8}{r \cos(\theta)}
\]
Step 3: Simplify the Equation
Multiply both sides by \( r \cos(\theta) \) to eliminate the fraction:
\[
r^2 \sin(\theta) \cos(\theta) = 8
\]
Step 4: Solve for \( r^2 \)
Isolate \( r^2 \) by dividing both sides by \( \sin(\theta) \cos(\theta) \):
\[
r^2 = \frac{8}{\sin(\theta) \cos(\theta)}
\]
Step 5: Use Trigonometric Identity
Use the trigonometric identity \( \sin(2\theta) = 2 \sin(\theta) \cos(\theta) \) to further simplify:
\[
r^2 = \frac{8}{\frac{1}{2} \sin(2\theta)} = \frac{16}{\sin(2\theta)}
\]