Question

Các bạn giúp mình nhanh nhanh câu này nha, mình cần gấp lắm á. c) 6x^4 + 25x^3 + 12x^2 - 25x + 6 = 0

Answer 1

\(\Leftrightarrow6x^4+12x^3+13x^3+26x^2-14x-28x+3x+6=0\)

\(\Leftrightarrow\left(x+2\right)\left(6x^3+13x^2-14x+3\right)=0\)

\(\Leftrightarrow\left(x+2\right)\left(6x^3+18x^2-5x^2-13x+x+3\right)=0\)

\(\Leftrightarrow\left(x+2\right)\cdot\left(x+3\right)\left(6x^2-5x+1\right)=0\)

\(\Leftrightarrow\left(x+2\right)\left(x+3\right)\left(2x-1\right)\left(3x-1\right)=0\)

hay \(x\in\left\{-2;-3;\dfrac{1}{2};\dfrac{1}{3}\right\}\)