Question

jo ye 3 formula ka matlab bata dega usko thanks, brainliest follow sab kar denge​

Answer 1

Lets first understand meaning of sigma ∑ , it denotes summation . Its subscript denotes from where summation is starting and superscript denotes to where it will end.

So basically formulae written is ∑sin(A + (r-1)B) which means , in this sin(A + (r-1)B) start putting r from 1 to n , and then add all the terms which you get.This comprises LHS and RHS is direct term.

So basically let me explain when and why we use this formula .

consider a question simplify sin(x) + sin(x+y) + sin(x+2y) ... till sin(x + ny) in this case we can use this formula here A=x B=y .

Similarly we can do for second formula.

Lets understand the meaning of π pi which denotes product. Its subscript denotes from where product is starting and superscript denotes to where it will end.

So it can also be written as :-

cosA * cos2A * cos4A ... till cos 2^(n-1)A this comprises LHS and RHS is a single term direct formula.

Hope it helps.