Sin Cos and Tan are symbols for equations where the sides of an a corner are equal to the symbol of that corner's degree
So the Sin of 60 degrees is equal to the Sin of a side length over another one.
We use Sin Cos and Tan on right triangles only however
So lets create a triangle with corner a being 60 degrees and corner 30 degrees
This is commonly know as the 30-60-90 triangle.
Every triangle is congruent to another. So in the above case, the 30-60-90 triangle could have side lengths : 3,4 and 5 or 6,8 and 10. These have the same angle measures but different side lengths. These triangles are congruent.
The equations of Sin Cos and Tan are as follows:
Sin = o/h
Cos=a/h
Tan=o/a
o is representation of opposite. This means the side opposite of Corner 1 goes in this place
a is a representation of adjacent. This is the side adjeacent to Corner 1
h is the hypoteneuse, or the side oppostie the 90 degree angle.
These equations help you find the side lengths or angle lenghts.
The Sin ^-1 Cos^-1 and Tan ^-1 are simply inverses of the original equations
So:
Sin^-1=h/o
Cos^-1=h/a
Tan^-1=a/o
That is pretty much it explained