SOLUTION: Representing one unit by at least five squares on your graph paper, draw the unit circle, which is centered at the origin and goes through point A = (1, 0). Use a protractor to mar

Question 1163981: Representing one unit by at least five squares on your graph paper, draw the unit circle, which is centered at the origin and goes through point A = (1, 0). Use a protractor to mark the third-quadrant point P on the circle for which arc AP has angular size 215 degrees. Estimate the coordinates of P, reading from your graph paper. Notice that both are negative numbers. Use a calculator to find the cosine and sine values of a 215-degree angle. Explore further to explain why sine and cosine are known as circular functions.
Answer by Edwin McCravy(20054) (Show Source): You can put this solution on YOUR website!

  

From 0 to -1 on each axis, I marked off in tenths, and it appears that
the marked point has coordinates approximately (-0.8,-,6).

On my calculator I find 

cos(215°) = -0.8191520443  
sin(215°) = -0.5735764364

Those are very near to the coordinates I estimated.  So that's why
sine and cosine are called "the circular functions".  They are the 
coordinates of the points on the unit circle. 

Edwin

RELATED QUESTIONS
find the area of the circle centered at the origin that passes through the point (-3,5) (answered by Fombitz)

Please help me with the following: A unit circle is centered at the origin undergoes... (answered by fractalier)

an equilateral triangle is inscribed in the circle of radius 1 centered at the origin... (answered by Alan3354)

An equilateral triangle is inscribed in the circle of radius 1 centered at the origin... (answered by ikleyn)

To start a new transport company, a business needs at least 5 buses and 10 minibuses. He (answered by Theo)

A circle is represented by the equation below: (x + 2)2 + (y - 4)2 = 225 Which... (answered by fcabanski)

find the coordinates of six points on a circle centered at the origin with a radiius of... (answered by solver91311)

The circle is centered at the origin and contains the point (-4,-2). What is the length... (answered by Alan3354)

Consider the function {{{f(x) = sqrt(4-x^2)}}} Hint: This is the upper half of a... (answered by KMST)