Решить 2 уравнения
1) a)1/tg²x+3/sinx+3=0 b)корни ур-я на [2p;7p/2]
2) a)1/sin²x-1/cos(3p/2-x)=2 b) корни ур-я на [p;5p/2]

1сos²x/sin²x+3/sinx+3=0sinx≠01-sin²x+3sinx+3sin²x=0sinx=a2a²+3a+1=0D=9-8=1a1=(-3-1)/4=-1⇒sinx=-1⇒x=-π/2+2πn,n∈z2π≤-π/2+2πn≤7π/24≤-1+4n≤75≤4n≤85/4≤n≤2n=2⇒x=-π/2+4π=7π/2a2=(-3+10/4=-1/2⇒sinx=-1/2x=-π/6+2πk,k∈z U x=7π/6+2πm,m∈z2π≤-π/6+2πk≤7π/212≤-1+12k≤2113≤12k≤2213/12≤k≤11/6нет решения2π≤7π/6+2πm≤7π/212≤7+12m≤215≤12m≤145/12≤m≤14/12m=1⇒x=7π/6+2π=16π/62sinx≠02sin²x-sinx-1=0sinx=a2a²-a-1=0D=1+8=9a1=(1-3)/4=-1/2⇒sinx=-1/2x=-π/6+2πk,k∈z U x=7π/6+2πm,m∈zπ≤-π/6+2πk≤5π/26≤-1+12k≤157≤12k≤167/12≤k≤4/3k=1⇒x=-π/6+2π=11π/6π≤7π+2πm≤5π/26≤7+12m≤15-1≤12m≤8-1/12≤m≤2/3m=0⇒x=7π/6a2=(1+3)/4=1⇒sinx=1⇒x=π/2+2πn,n∈zπ≤π/2+2πn≤5π/22≤1+4n≤51≤4n≤41/4≤n≤1n=1⇒x=π/2+2π=5π/2