Question

1/sin^2x+ctgx-3<0 pomogite pleaseee

Answer 1

1+ctg²x-ctgx-3<0
ctg²x-ctgx-2<0
a=ctgx
a²-a-2<0
a1+a2=1 U a1*a2=-2⇒a1=2 U a2=-1
     +            _                +
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           -1                2
-1<a<2
-1<ctgx<2
-3/4π+πn<x<arcctg2+πn
x∈(-3/4π+πn;arcctg2+πn)