a) 4x^2 – 12x+9
b) 9x^2 – 24 xy+16y^2
c)4x^2+4x+4
d)x^2/4 + 2xy+4y^2
e) (3x-1)^2 – 16
f)(5x-4)^2 – 49x^2
g) 8x^3 – 64
h ) 125x^3 – 1
i)27x^3+y^2/8
j)123^3+27y
phân tích đttnt
a) 4x^2 – 12x+9
b) 9x^2 – 24 xy+16y^2
c)4x^2+4x+4
d)x^2/4 + 2xy+4y^2
e) (3x-1)^2 – 16
f)(5x-4)^2 – 49x^2
g) 8x^3 – 64
h ) 125x^3 – 1
i)27x^3+y^2/8
j)123^3+27y
phân tích đttnt
Đáp án:
Giải thích các bước giải:
a/ $4x^2-12x+9=(2x-3)^2$
b/ $9x^2-24xy+16y^2=(3x-4y)^2$
c/ $4x^2+4x+4=4(x^2+x+1)$
d/ $\frac{x^2}{4}+2xy+4y^2=(\frac{x}{2}+2y)^2$
e/ $(3x-1)^2-16=(3x-1-4)(3x-1+4)=(3x-5)(3x+3)$
f/ $(5x-4)^2-49x^2$
$=(5x-4+7x)(5x-4-7x)$
$=(12x-4)(-2x-4)=4(3x-1).(-2)(x+2)$
$=-8(3x-1)(x+2)$
g/ $8x^3-64=(2x-4)(4x^2+8x+16)=2(x-2)(4x^2+8x+16)$
h/ $125x^3-1=(5x-1)(25x^2+5x+1)$
i/ $27x^3+\frac{y^3}{8}=(3x+\frac{y}{2})(9x^2-\frac{1}{2}.3xy+\frac{y^2}{4})$
j/ $123^3+27y^3=(123+3y)(123^2-369y+9y^2)$
Chúc bạn học tốt !!!