Đề bài: Phân tích đa thức thành nhân tử:
1. x + 6\(\sqrt{x}\) + 8
2. x - 2\(\sqrt{x}\) - 3
3. 11 + \(\frac{9}{16}\) a
4. \(x^2\) - 2\(\sqrt{2}\) x + 2
5. \(x^2\) + 2\(\sqrt{13}\) x + 13
6. \(\frac{1}{8}\) x \(\sqrt{x}\) - \(\frac{1}{2}x\sqrt{y}\) + \(\frac{2}{3}y\sqrt{x}\) - \(\frac{8}{27}y\sqrt{y}\) - 8
Các cậu giúp tớ nhé! Tớ cảm ơn nhiều!!!!
\(1.\)
\(x+6\sqrt{x}+8\\ =\sqrt{x}^2+2\sqrt{x}.3+9-1\\ =\left(\sqrt{x}+3\right)^2-1\\ =\left(\sqrt{x}+2\right)\left(\sqrt{x}+4\right)\)
\(2.\)
\(x-2\sqrt{x}-3\\ =\sqrt{x}^2-2\sqrt{x}+1-4\\ =\left(\sqrt{x}-1\right)^2-2^2\\ =\left(\sqrt{x}-3\right)\left(\sqrt{x}+1\right)\)
\(4.\)
\(x^2-2\sqrt{2}x+2\\ =\left(x-\sqrt{2}\right)^2\)
\(5.\)
\(x^2+2\sqrt{13}x+13=\left(x+\sqrt{13}\right)^2\)
