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((х-5)(х+5))2+((х+5)(х-2))2=0 => (х-5)2*(х+5)2+(х+5)2*(х-2)2=0 => (х+5)2*((х-5)2+(х-2)2)=0 =>
(х+5)2=0 и ((х-5)2+(х-2)2)=0-не имеет решений => х=-5
Ctg 56 * tg 56 = 1 ......
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3x² = 12
x² = 4
x₁ = 2 x₂ = - 2
y₁ = 7 - x² = 7 - 2² = 7 - 4 = 3
y₂ = 7 - x² = 7 - (- 2)² = 7 - 4 = 3
Ответ : (2 ; 3) , (- 2 ; 3)