[tex]cos \alpha = \frac{1 }{2} [/tex]

[tex]sin \alpha = \frac{1}{4} [/tex]
поможіть !!!)

1)@=+-arccos(1/2)+2pik

@=+-pi/6+2pik

2)@=arcsin(1/4)+2pik  @=pi-arcsin(1/4)+2pik