In Brazil, the locals (25)_ the myth of the mermaid Lara who lives in the Amazon River. One night, a young man dreamed of a beautiful woman (26)_ a sad song. The next day, he went fishing with his father and saw the woman in his dream in a hut floating on the water. She sang to him and he went to her. Too late, the man’s father saw that the woman had the long tail (27)_ a pink dolphin. She grabbed the young man and dived into the water with him. His father never saw him again. To this day, the locals still say that they sometimes see the mermaid swimming deep in the water. And when they hear the sad song of the mermaid Lara, they (28)_ their doors and stay far away from the river.

a) Viết công thức tính công thức tính áp suất chất rắn, nêu tên và đơn vị của các đại lượng trong công thức

(x-2)^2 - (x-3) (x+3) = 5 là x =

4x + 5/ 16x^2 - 25 tại x = 1

Kết quả rút gọn biểu thức (2x - 3) (4x^2 + 6x + 9) - 2 ( 4x^3 - 25) là x = 

x(x - 2)+(x + 5 )(x^2 - x + 1) tại x = 1, tính giá trị biểu thức

x^2( x + 4) - (x  + 5)(x^2 - x + 1) rút gọn biểu thức

Gía trị biểu thức x^2 - 2xy + y^2 + 3 tại x = 63, y = 3 là

(x + 2) (x(x^2 - 2x + 4) - x(x^2 +2) = 15, Tính giá trị x thỏa mãn