1- sin2x=(cos2x+sin2x)²
1- sin2x=cos²2x+sin²2x+2sin2xcos2x
1- sin2x=1+2sin2xcos2x
- sin2x-2sin2xcos2x=0
-sin2x(1+cos2x)=0
sin2x=0 ; 1+cos2x=0
2x=πk cos2x=-1
x=πk/2;k∈Z 2x=π+2πk
x=π/2+πk;k∈Z
2) log₀,₅(х-1)+log₀,₅(х-2)≥-1; ОДЗ: x>2
log₀,₅(х-1)(х-2)≥-1log₀,₅0,5
log₀,₅(х-1)(х-2)≥log₀,₅2
(x-1)(x-2)≤2
x²-3x≤0
x(x-3)≤0
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С учётом ОДЗ х∈(2;3]
Ответ:х∈(2;3]