How do you convert (2,π4) into rectangular coordinates?

2 Answers
Jan 18, 2016

x=2cos(π4)=20.707=1.414

y=2sin(π4)=20.707=1.414

Rectangular coordinates are (1.4,1.4)

Explanation:

These coordinates describe a line 2 units long, starting at the origin, (0,0), at an angle of π4 radians anticlockwise (counterclockwise) from the positive axis.

Some find it easier to work in radians, some in degrees. π4 is 45o. I'll keep working in radians, since that is how the question is set up.

For rectangular coordinates we need to find the distance of the projection along the x-axis for the first point and along the y-axis for the second.

Draw a diagram. It's crucial.

Now use the definition of trigonometry. The two points are as follows:

x=2cos(π4)=20.707=1.414

y=2sin(π4)=20.707=1.414

Jan 18, 2016

(2,2)

Explanation:

Using the formulae that links Polar and Cartesian coordinates .

x=rcosθ

y=rsinθ

here r = 2 , θ=π4

x=2cos(π4)=2.12=22×22=2

and y = 2sin(π4)=2.12=2