Question

giai pt

3x-7can x +4 =0

Answer 1

\(3x-7\sqrt{x}+4=0\)

\(\left(3x-3\sqrt{x}\right)-\left(4\sqrt{x}-4\right)=0\)

\(3\sqrt{x}\left(\sqrt{x}-1\right)-4\left(\sqrt{x}-1\right)=0\)

\(\left(\sqrt{x}-1\right)\left(3\sqrt{x}-4\right)=0\)

\(\orbr{\begin{cases}x=1\\x=\frac{16}{9}\end{cases}}.\)

Answer 2

Dễ mà:

           3x-7Vx +4=3x-3Vx-4Vx+4=3Vx(Vx-1)-4Vx(Vx-1)=(Vx-1)(3Vx-4)=0

                                =>x=1,16/9

Note : V là căn