# How to create a sine wave with a given angle between the side of the wave?

I want to create this shape using Illustrator CC and maybe it could seem easy but actually it has to be perfect, the shape are basically two triangles and each one of them with 52 degrees of aperture.

I've been trying to using the rotate tool but it's still imperfect and even if I leave it like that the rounded part looks awful (2). I tried with the Pen Tool and try to reshape the form with the sketch but still don't get the results that I want and with the rounded form I tried with the Shape Builder Tool (1).

Could someone please help me? Should I create the form on paper (perfect, with rulers, pencils and stuff) and then digitalise it? And if that's how it suppose to work, the angles will be the same?

The shape you are trying to duplicate is difficult to draw.
It is a mathematical function called a sine wave.

I use a different version of Illustrator but the technique to draw one is the same or very similar. Things in Adobe programs migrate from menu to menu so I'll have to tell you what to do by name.

Draw a line.
Select it.
Apply "Zig-Zag" effect.
Options:
Try using the size you prefer in either % or in absolute measurement.
Ridges per segment is 1.5
Points should be smooth.

That should get you pretty close, pretty quickly.

• Or you can graph a sinewave (scroll down for sine wave tutorial) Commented Jul 17, 2016 at 10:34
• If one wants a 52 degree 0 crossing tangent then plot the function `(0.487733 * t, sin( t )` (result as image) Commented Jul 17, 2016 at 11:28
• @Joojaa That's nice. How does one do the plotting using Adobe Illustrator to do this? What software did you use?
– Stan
Commented Jul 17, 2016 at 14:34
• Thats the first link i gave you in the first answer. how to use Commented Jul 17, 2016 at 14:40
• @joojaa PLEASE put that as an answer so that I can vote it up. That solved a problem for me to illustrate damped functions
– Stan
Commented Jul 17, 2016 at 14:53

Create a sharp, no rounded corners, zigzag of exactly the 52 degrees in/out you need, with as many iterations as you need.

Draw a single circle at one of the vertices(points) at the size you want for reference.

Now select all the vertices (points) on your zig zag, and round them as much as you want to get as close to the circle as you like, or otherwise.