list of all the angles of trigonometry : angle 18 ,angle 15,angle 36,angle 54,angle75

Not Clear, Please post question completely!

Trigonometry is the chapter of class 10. The degree of all the ratios are not given in the book. But we use the given formulas and apply him (90-A)

Sorry i dont know this

In the NCERT maths textbook only the angles of 0,30,45,60 and 90 are given. So if angles other than these are given we should use (90-given angle) which is also one of our topic in textbook. There are sums related to these problems too. Hope this information helps you:-)