^ * forall x in mathbb R .; x^ 2 5x Rightarrow x - Dicamon

Question

^ * forall x in mathbb R .; x^ 2 >5x Rightarrow x>5^ prime; 12. forall x in mathbb R .x^ 2 <4x Rightarrow x<4

Answer

x ^ 2 2 Dung 2 <=4x; x ^ 2 - 4x < 0; 0 < x < 4

Answer

forall x in IR; x ^ 2 > 5x; x(x - 5) > 0; x > 0x > 5; x < 0; x - 5 < 0 ) forall x in R; x ^ 2 < 4x; x ^ 2 - 4x < 0; x(x - 4) < 0 ) x > 0; |x-4<0 <4 0 < x < 4; x < 0; k < 0; x > 4;

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