Question

[Nhã Phương]

Rút gọn :

a) 2√25xy + √225x^3y^3 - 3y√16x^3y( x,y >=0)

b) -√36b - 1/3√54b + 1/5√150b ( b>= 0)

Tìm x br :

a) √16-32x -√12x=√3x + √9-18x

( giúp mk gấp w tnay mk pk nộp bài rồi . Thk các bn )

Answer 1

[Phùng Khánh Linh]

\(1a.2\sqrt{25xy}+\sqrt{225x^3y^3}-3y\sqrt{16x^3y}=10\sqrt{xy}+15xy\sqrt{xy}-12xy\sqrt{xy}=10\sqrt{xy}+3xy\sqrt{xy}=\sqrt{xy}\left(10+3xy\right)\left(x,y\ge0\right)\)

\(b.-\sqrt{36b}-\dfrac{1}{3}\sqrt{54b}+\dfrac{1}{5}\sqrt{150b}=-6\sqrt{b}-\sqrt{6b}+\sqrt{6b}=-6\sqrt{b}\left(b\ge0\right)\)

\(2.\sqrt{16-32x}-\sqrt{12x}=\sqrt{3x}+\sqrt{9-18x}\)

\(\Leftrightarrow4\sqrt{1-2x}-2\sqrt{3x}-\sqrt{3x}-3\sqrt{1-2x}=0\)

\(\Leftrightarrow\sqrt{1-2x}=4\sqrt{3x}\left(x\ge\dfrac{1}{2}\right)\)

\(\Leftrightarrow1-2x=48x\)

\(\Leftrightarrow x=\dfrac{1}{50}\left(KTM\right)\)

KL....