Question

Phân tích đa thức thành nhân tử:

a) 3x²+2x-5

b)25x²-12x-13

Answer 1

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

b) \(25x^2-12x-13=25x\left(x-1\right)+13\left(x-1\right)=\left(x-1\right)\left(25x+13\right)\)

Answer 2

a) \(3x^2+2x-5\)

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

\(=\left(\sqrt{2}x\right)^2-\left(-\left(x\right)^2-2x+\left(1\right)^2\right)-4\)

\(=\left(\sqrt{2}x\right)^2-\left(-x-1\right)^2\)

\(=\left(\sqrt{2}.x+x+1\right)\left(\sqrt{2}.x-x-1\right)\)