cos(x/6)cos(x/3)

Solution for cos(x/6)cos(x/3) equation:

x in (-oo:+oo)

cos(x/6)*cos(x/3) = 0

cos(x/6) = 0

cos(x/6) = 0  <=>  x/6 = pi*k_1+pi/2 i k_1 należy do I

t_1 = pi*k_1+pi/2

x/6-t_1 = 0

1/6*x-t_1 = 0 // + t_1

1/6*x = t_1 // : 1/6

x = t_1/1/6

x = 6*t_1

x = 6*pi*k_1+pi/2 i k_1 należy do I

cos(x/3) = 0

cos(x/3) = 0  <=>  x/3 = pi*k_2+pi/2 i k_2 należy do I

t_2 = pi*k_2+pi/2

x/3-t_2 = 0

1/3*x-t_2 = 0 // + t_2

1/3*x = t_2 // : 1/3

x = t_2/1/3

x = 3*t_2

x = 3*pi*k_2+pi/2 i k_2 należy do I

cos(x/6)*cos(x/3) = 0  <=>  cos(x/6) = 0 or cos(x/6)*cos(x/3) = 0  <=>  cos(x/3) = 0

x in { 6*pi*k_1+pi/2, 3*pi*k_2+pi/2 }