1. The gymnast isn't short. She's ...tall...

2. She isn't fat. She's ...slim...

3. She isn't weak. She's ...strong...

4. Mrs. Hong isn't young. She's ...old...

5. She isn't strong. She's ...weak...

6. She isn't heavy. She's ...light...

7. Quan is young. He isn't ...old...

8. He isn't small and weak. He's very ...big... and ...strong...

\(=x^2+2.x\cdot\frac{\sqrt{3}}{2}+\frac{3}{4}+\frac{1}{4}=\left(x+\frac{\sqrt{3}}{4}\right)^2+\frac{1}{4}\)

Vậy GTNN là 1/4 khi \(x+\frac{\sqrt{3}}{2}=0\Rightarrow x=-\frac{\sqrt{3}}{2}\)

có 9 cách chọn chữ số hàng trăm triệu và 9 cách chọn chữ số hàng chục triệu =>m=9*9*9*9*9*9*9*9*9=9^9.

Mà 9^9=9*9^8=>9*9^8<10*9^8.Vậy m<10*9^8