Question

Bài 1 Tìm nghiệm

a, P(x)=(x-3).(x+4)

b,Q(x)=(1/3x-1).(2x-3/5)

giup mk vs

Answer 1

a/ P(x) = (x - 3)(x + 4)

Ta có: (x - 3)(x + 4) = 0

\(\Rightarrow\left[{}\begin{matrix}x-3=0\\x+4=0\end{matrix}\right.\Rightarrow\left[{}\begin{matrix}x=3\\x=-4\end{matrix}\right.\)

Vậy................................

b/ Q(x) = \(\left(\dfrac{1}{3}x-1\right)\left(2x-\dfrac{3}{5}\right)\)

Ta có: \(\left(\dfrac{1}{3}x-1\right)\left(2x-\dfrac{3}{5}\right)=0\)

\(\Rightarrow\left[{}\begin{matrix}\dfrac{1}{3}x-1=0\\2x-\dfrac{3}{5}=0\end{matrix}\right.\Rightarrow\left[{}\begin{matrix}\dfrac{1}{3}x=1\Rightarrow x=3\\2x=\dfrac{3}{5}\Rightarrow x=\dfrac{3}{10}\end{matrix}\right.\)

Vậy................................