b2=-2*1/(-5)=2/5=0.4
b3=-2*1/0.4=-2/0.4=-(20/4)= -5
Ответ: -5
F'(x) = (cos5x)'(cos3x)+(cos3x)'(cos5x) + (sin5x)'(sin3x)+(sin3x)'(sin5x)-x' =
-5sin5xcos3x-3sin3xcos5x +5cos5xsin3x+3cos3xsin5x-1 = 2sin3xcos5x -2sin5xcos3x - 1=
-2(sin5xcos3x- sin3xcos5x) -1 =
-2sin2x-1
V 6 • ( V 24 - V 54 ) = V 6 • ( ( 2 V 6 ) - ( 3 V 6 ) ) = V 6 • ( - V 6 ) = - 6