Question

sin(-330)cos(-300)+sin(-420)cos(390)
=-1/2
​

Answer 1

Answer:

-1/2

Sin(30-60)= -sin30 =-1/2

sin (-330) = sin(30)

cos(-300) = cos 60

Sin(-420) = Sin(-60) = -sin(60)

Cos(390) = Cos(30)

Step-by-step explanation:

use formalue for sin(a-b)