Cos²x=1:(1+tg²x)=1:(1+4/9)=9/13
cosx=+-3/√13
sinx=+-√1-cos²x)=+-√(1-9/13)=+-√(4/13)=+-2/√13
sin2x=2sinxcosx=2*2√13*3/√13=12/13
cos2x=cos²x-sin²x=9/13-4/13=5/13
sin(2x+π+π/4)=-sin(2x+π/4)=-sin2x*cosπ/4-cos2x*sinπ/4=
=-12/13*√2/2-5/13*√2/2=-√2/2*(12/13+5/13)=-√2/2*17/13=-14√2/26