Trigonometric circle

Trigonometric circle

1. It is that circle whose center coincides with the coordinate origin of the plane Cartesian and radius measures unity.

   • Angle in normal position
     • At a trigonometric angle in position normal, the vertex must be at the origin of coordinates and the starting side must match with the positive side of the X axis
   • Coterminal angle
     • Two or more angles are called initial coterials, when they have the same side initial and the same final side, the difference of these angles is the number of turns on the side.
       • Quadrants of the trigonometric circle
         • By dividing the circle into 4 equal parts, each part is known as a quadrant, in each quadrant the sine, cosine, tangent and cotangent functions change their value.
   • Reference angle
     • A reference angle is an angle positive acute representing an angle θ of any size.