Question

либо 4 либо 5 номер.

Answer 1

4
cosa=-√(1-sin²a)=-√(1-144/169)=-√(25/169)=-5/13
tga=sina/cosa=-12/13:(-5/13)=12/13*13/5=12/5
tg(a-π/4)=(tga-tgπ/4)/(1-tga*tgπ/4)=(12/5-1):(1+12/5*1)=
=7/5*5/17=7/17
5
sinx≥-1/2
x∈(-π/6+2πn;7π/6+2πn,n∈z)

ctgx<-1/√3
x∈(2π/3+πn,π+πn,n∈z)

Answer 2

Ответ &/$#@//[email protected]/^[email protected]@///[email protected]@(*&^[email protected]^()*/#@!