Question

[Mưa Bong Bóng]

bài 1: phân tích thành nhân tử

a) \(^{6x^2}\)+ 9x b) \(4x^2\) + 8x c) \(5x^2\) + 10x

d) \(2x^2\)- 8x e) 5x - 15y f) x (\(x^2\)-1) + 3 (\(x^2\)-1)

g) \(x^2\)- 2x + 1 - \(4y^2\) h) \(x^2\)- 100 i) \(9x^2\)- 18x + 9

k) \(x^3\) - 8 l) \(x^2\)+ \(6xy^2\) + \(9y^4\) m) 4xy - \(4x^2\) - \(y^2\)

n) \(\left(x-15\right)^2\) - 16 o) 25 - \(\left(3-x\right)^2\) p) \(\left(7x-4\right)^2\)- \(\left(2x+1\right)^2\)

Bài 2: phân tích thành nhân tử

a) \(3x^3\) - \(6x^2\) + 3\(x^2y\) - 6xy b) \(x^2\) - 2x + xy -2y

c) 2x + \(x^2\) -2y - 2xy + \(y^2\) d) \(x^2\) - 2xy + \(y^2\) - 9

e) \(x^2\)+ \(y^2\) - 2xy -4 f) 2xy - \(x^2\)- \(y^2\) + 9

h) \(x^2\)- \(y^2\) + 12y - 36 i) \(4x^2\) - 9 - x(2x - 3)

bài 3: tìm x

a) 2(x + 3) - \(x^2\) -3x = 0 b) \(x^3\) - 25x= 0

c) 5(x-9) + \(x^2\) -9x = 0 d) 2(x + 5) - \(x^2\) -5x = 0

e) (2x + 3)(x - 1) + (2x-3)(1 - x) = 0 f) \(x^3\) + \(x^2\) + x + 1 = 0

h) 2x(x + 3) = x+3 i) \(x^2\)(x - 5) - 4x+ 20 = 0

Answer 1

[Hà Linh]

Dài dữ trời :V Về sau gửi từng bài một thôi, nhìn hoa mắt quá @@

B1: Phân tích thành nhân tử:

a) \(6x^2+9x=3x\left(2x+3\right)\)

b) \(4x^2+8x=4x\left(x+2\right)\)

c) \(5x^2+10x=5x\left(x+2\right)\)

d) \(2x^2-8x=2x\left(x-4\right)\)

e) \(5x-15y=5\left(x-3y\right)\)

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

\(=\left(x-1\right)\left(x+1\right)\left(x+3\right)\)

g) \(x^2-2x+1-4y^2=\left(x-1\right)^2-4y^2\)

\(=\left(x-1-2y\right)\left(x-1+2y\right)\)

h) \(x^2-100=\left(x-10\right)\left(x+10\right)\)

i) \(9x^2-18x+9=\left(3x-3\right)^2\)

k) \(x^3-8=\left(x-2\right)\left(x^2+2x+4\right)\)

l) \(x^2+6xy^2+9y^4=\left(x+3y\right)^2\)

m) \(4xy-4x^2-y^2=-\left(4x^2-4xy+y^2\right)\)

\(=-\left(2x-y\right)^2\)

n) \(\left(x-15\right)^2-16=\left(x-15-16\right)\left(x-15+16\right)\)

\(=\left(x-31\right)\left(x+1\right)\)

o) \(25-\left(3-x\right)^2=\left(5-3+x\right)\left(5+3+x\right)\)

\(=\left(2+x\right)\left(8+x\right)\)

p) \(\left(7x-4\right)^2-\left(2x+1\right)^2\)

\(=\left(7x-4-2x-1\right)\left(7x-4+2x+1\right)\)

\(=\left(5x-5\right)\left(9x-3\right)\)

Answer 2

[DƯƠNG PHAN KHÁNH DƯƠNG]

Bài 1 :

a ) \(6x^2+9x=3x\left(x+3\right)\)

b ) \(4x^2+8x=4x\left(x+2\right)\)

c ) \(5x^2+10x=5x\left(x+2\right)\)

d ) \(2x^2-8x=2x\left(x-4\right)\)

e ) \(5x-15y=5\left(x-3y\right)\)

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

g ) \(x^2-2x+1-4y^2=\left(x-1\right)^2-\left(2y\right)^2=\left(x-1-2y\right)\left(x-1+2y\right)\)

h ) \(x^2-100=x^2-10^2=\left(x-10\right)\left(x+10\right)\)

i ) \(9x^2-18x+9=\left(3x-3\right)^2\)

k ) \(x^3-8=\left(x-2\right)\left(x^2+2x+2^2\right)\)

l ) \(x^2+6xy^2+9y^4=\left(x+3y^2\right)^2\)

m ) \(4xy-4x^2-y^2=-\left(2x-y\right)^2\)

n ) \(\left(x-15\right)^2=x^2-30x+15^2\)

o ) \(25-\left(3-x\right)^2=\left(5-3+x\right)\left(5+3-x\right)=\left(2+x\right)\left(8-x\right)\)

p ) \(\left(7x-4\right)^2-\left(2x+1\right)^2=\left(7x-4-2x-1\right)\left(7x-4+2x+1\right)=\left(5x-5\right)\left(9x-3\right)\)

Bài 2 :

a ) \(3x^3-6x^2+3x^2y-6xy=3x\left(x^2-2x+xy-2y\right)\)

b ) \(x^2-2x+xy-2y=x\left(x-2\right)+y\left(x-2\right)=\left(x-2\right)\left(x+y\right)\)

c ) \(2x+x^2-2y-2xy=......................\)

d ) \(x^2-2xy+y^2-9=\left(x-y\right)^2-3^2=\left(x-y-3\right)\left(x-y+3\right)\)

e ) \(x^2+y^2-2xy-4=\left(x-y\right)^2-2^2=\left(x-y-2\right)\left(x-y+2\right)\)

f )\(2xy-x^2-y^2+9=-\left(x-y\right)^2+9=3^2-\left(x-y\right)^2=\left(3-x+y\right)\left(3+x-y\right)\)