Giống lớp $6$ nhỉ
$A = \left\{ x \in \mathbb{N} \mid x \leqslant 4 \right\}$
$B = \left\{ x \in \mathbb{N} ; x \leqslant 4 \mid 4x \right\}$
$C = \left\{ x \in \mathbb{N^*} ; x \leqslant 4 \mid (-3)^x \right\}$
$D = \left\{ x \in \mathbb{N^*} ; x \leqslant 4 \mid 9x^2 \right\}$
$E = \left\{ x \in \mathbb{P} \mid x \leqslant 11 \right\}$
$F = \left\{ x \in \mathbb{N^*} ; x \leqslant 5 \mid 3x \right\}$
$G = \left\{ x, y \in \mathbb{R} ; \sqrt{(x-x_A)^2 + (y-y_A)^2} = \sqrt{(x-x_B)^2 + (y-y_B)^2} \mid (x;y) \right\}$
Không thấy rõ bán kính, thay đại $=R$ nhé
$H = \left\{ x,y \in \mathbb{R} ; \sqrt{(x-x_I)^2 + (y-y_I)^2} = R \mid (x;y) \right\}$