Trigonometry Examples

$(4, 90)$

Step 1

Use the conversion formulas to convert from polar coordinates to rectangular coordinates.

$x = r c o s θ$

$y = r s i n θ$

Step 2

Substitute in the known values of $r = 4$ and $θ = 90$ into the formulas.

$x = (4) \cos (90)$

$y = (4) \sin (90)$

Step 3

The exact value of $\cos (90)$ is $0$ .

$x = 4 \cdot 0$

$y = (4) \sin (90)$

Step 4

Multiply $4$ by $0$ .

$x = 0$

$y = (4) \sin (90)$

Step 5

The exact value of $\sin (90)$ is $1$ .

$x = 0$

$y = 4 \cdot 1$

Step 6

Multiply $4$ by $1$ .

$x = 0$

$y = 4$

Step 7

The rectangular representation of the polar point $(4, 90)$ is $(0, 4)$ .

$(0, 4)$