Question

СРОЧНО ПОМОГИТЕ, ТРИГОНОМЕТРИЯ

Answer 1

1)sin(x-pi)=V2/2

sinx*cos(pi)-cosx*sin(pi)=V2/2

-sinx=V2/2

sinx=-V2/2

x1=5pi/4; x2=-pi/4+2pi=7pi/4

2)sin(6x)-cos(6x)=V2

cos(6x)=sin(6x+pi/2)-подставлю

sin(6x)-sin(6x+pi/2)=V2

2sin(-pi/4)*cos(6x+pi/4)=V2

-2*V2/2*cos(6x+pi/4)=V2

cos(6x+pi/4)=-1

6x+pi/4=pi+2pik

6x=3pi/4+2pik

x=pi/8+pik/3; k∈Z