Class 11 &12 maths important formula of trigonometry

The formula of freon -12 is :

Prove by vector metod the following formula of plane trigonometry cos(alpha-beta)=cosalpha cosbeta+sinalpha sinbeta

Chemical formula of Freon 12 is

Which is the correct formula of freon 12?

Class 10 Maths Ex 9.1 examples (Part 2) Ch 9 Some Applications of Trigonometry (Heights & Distances)

Class- 7 Math profit and loss

Class 12 maths ncert solution chapter vector algebra Ex-10.2 Qno.1

Why are symbols and formulae of substances important ?

List the name and formulae of two important ores of copper.