``` E: BTVN a) (1/2 + 1/7) * (2/21 - 5/7) b) 3/5 * (7/15 + 1/5) / (-1/3 - 1/15) c) [6 + 2 * (3^3 - 47)] * 2 d) (2/3 + 1/2)² * (5/5 - 1/5) ```

----- Nội dung ảnh -----
Bức ảnh có nội dung như sau:

```
E: BTVN
a) (1/2 + 1/7) * (2/21 - 5/7)
b) 3/5 * (7/15 + 1/5) / (-1/3 - 1/15)
c) [6 + 2 * (3^3 - 47)] * 2
d) (2/3 + 1/2)² * (5/5 - 1/5)
```