Question

cos4x * cos6x - cos5x=0 

 решите

 

Answer 1

cos 4x*cos 6x=0.5(cos10x+cos2x)

0.5cos10x+0.5cos2x-cos5x=0

0.5(2cos^2(5x)-1)+0.5cos2x-cos5x=0

cos^25x-1+0.5cos2x-cos5x=0

Прости Дима.