Объяснение:
sin(x+270°)-cos(3x+720°)=-cosx+cos3x=cos3x-cosx=-2sin2xsinx
sin(x+270°)=-cosx;
cos(3x+720°)=cos(3x+2*360°)=cos3x;
sin(x+270°)-cos(3x+720°)=-2sin2xsinx
Объяснение:
sin(x+270°)-cos(3x+720°)=-cosx+cos3x=cos3x-cosx=-2sin2xsinx
sin(x+270°)=-cosx;
cos(3x+720°)=cos(3x+2*360°)=cos3x;
sin(x+270°)-cos(3x+720°)=-2sin2xsinx