This applet shows how the graphs of sin (θ) and cos (θ) follow directly from the definition of these functions. Move the slider to change the angle. Observe that after the point moves once around the ...

Anna F. DeJarnette, Students' Conceptions of Sine and Cosine Functions When Representing Periodic Motion in a Visual Programming Environment, Journal for Research in Mathematics Education, Vol. 49, No ...

Dorothea D. Bone, SINE AND COSINE FUNCTIONS WITH A CALCULATOR, The Mathematics Teacher, Vol. 73, No. 7 (October 1980), pp. 521-524, 529 ...

Meanwhile trigonometry focuses on functions that depend on angles. These functions, such as the sine and cosine, are defined using right triangles.