Question

tính giá trị x thoả mãn

2x^2 + 3(x-1)(x+1)=5x(x+1)

Answer 1

Ta có :

\(2x^2+3\left(x-1\right)\left(x+1\right)=5x\left(x+1\right)\)

\(\Leftrightarrow2x^2+3x^2-3=5x^2+5x\)

\(\Leftrightarrow2x^2+3x^2-3-5x^2-5x=0\)

\(\Leftrightarrow-3-5x=0\)

\(\Rightarrow x=-\dfrac{3}{5}\)

Vậy \(x=-\dfrac{3}{5}\)

Answer 2

2x² + 3(x-1)(x+1)=5x(x+1)

2x² + 3(x² - 1) = 5x² + 5x

2x² + 3x² - 3 - 5x² - 5x = 0

-3 - 5x = 0

5x = -3

x = \(\dfrac{-3}{5}\)