Basically you have noticed trigonometry deals with triangles. But its beyond that.You can see it's deals with circles and more. Trig Identities Calculator is an online tool to find sine, cosine, tangent, secant, cosecant and cotangent of a right triangle. Trigonometry is a part of mathematics which is developed from geometrical measurement. It's also deals with triangles,circles etc. Know More About How to Find Circumference of a Circle