\(3x^2+x-2\)
=\(3x^2+3x-2x-2\)
=\(3x\left(x+1\right)-2\left(x+1\right)\)
=\(\left(3x-2\right)\left(x+1\right)\)
3x2+x-2
=3x2+3x-3x+x-2
=3x2+3x-2x-2
=3x.(x+1)-2(x+1)
=(x+1).(3x-2)
"₫e bai" ghi ro pp, hdt. "
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A=3x^2 +x-2
12A=36x^2+12x-24
12A=(6x)^2 +2.(6x)+1-25
=(6x+1)^2-5^2
=(6x+1-5)(6x+1+5)
=2.6.(3x-2)(x+1)
A=(3x-2)(x+1)
\(3x^2\)+x-2
=\(3x^2\)+3x-3x+x-2
=\(3x^2\)+3x-2x-2
=3x.(x+1)-2(x+1)
=(x+1).(3x-2)