1) cos a cos 3a - sin a sin 3a = cos (a+3a) = cos 4a
2) sin 2a cos a + cos 2a sin a = sin (2a+a) = sin 3a
3) sin40°cos5°+cos40°sin5° = sin(40°+5°)= sin 45° =
4)
5)
F(x)'=((1/5)*x⁵-1/x⁴+2)'=(1/5)*5x⁴-(-4)*x⁻⁴⁻¹+0=x⁴+4*x⁻⁵=x⁴+4/x⁵
(ED-EF)+(DM+MK)+x=(PK-PC)+FA
FD+DK+x=CK+FA
FK+x=CK+FA
x=CK+(FA-FK)
x=CK+KA
x=CA