Question

let alpha and beta be such that pi

Answer 1

(cos alpha+ cos beta) sq + ( sin alpha + sin beta ) sq
= ( -27/65)sq + (- 21/65)sq
=2 + 2 ( cos alpha cos beta + sin alpha sin beta ) = 1170/65sq
= 2 (1 +cos ( alpha - beta) ) = 1170/65sq
= 4 cos sq ( alpha - beta / 2 ) = 1170/ 65sq
=2 cos( alpha- beta/2) = - undr root 1170 /65
= cos ( alpha - beta/2) = undr root 1170/130
= - undr root 9.130/ 130 = - 3/ undr root 130
ANSWER A is correct

Answer 2

Answer:

this is short process and clear process