Question

if 8x=π,show that cos7x+cosx=0.

Answer 1

Answer:

Step-by-step explanation:

8x= 22/7

x=22/56

cos7x+cosx= cos 7*22/56+cos 22/56

                   = cos 22/8 + cos 22/56

                    = -0.92+0.92

                    = 0