Question

Câu 14: (1 điểm) Phân tích đa thức sau thành nhân tử

a) ${{x}^{2}}+25-10x$;                                      

b) $-8{{y}^{3}}+{{x}^{3}}$.

Answer 1

 

Answer 2

a).x^2+25-10x=x^2-10x+25=(x-5)^2

b).-8y^3+x^3=x^3-8y^3=(x-2y)(x^2+2xy+4y^2).

Answer 3

a/ \(x^2+25-10x\)                  b/ \(-8y^3+x^3\)

= \(x^2-10x+25\)                     = \(x^3-8y^3\)

= \(x^2-2.x.5+5^2\)                   = \(x^3-\left(2y\right)^3\)

= \(\left(x-5\right)^2\)                              = \(\left(x-2y\right)\left[x^2+x.2y+\left(2y\right)^2\right]\)

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

Answer 4

a)x²-10x+25=x²-2.x.5+5²

=(x-5)²

b)(-8y+x).(-8y-8y.x+x)=(-8y+x).(-8y-8xy+x)

Answer 5

a) x² + 25 - 10x = x² - 10x + 25 = (x)² - 2 . x . 5 + 5² = (x - 5)²

b) -8y³ + x³ = (-2y)³ + (x)³  = (-2y + x) (4y² - (-2xy) + x²)
                                            = (-2y + x) (4y² + 2xy + x²)

Answer 6

a) x² + 25 - 10x = x² - 10x + 25

                          = x² - 2.x.5 + 5²

                               = ( x - 5) ²

b) - 8y³ + x³ = ( - 2y ) ³ + x³

                     = ( -2y + x) ( 4y² - 2xy + x² )

                     

Answer 7

a) x^2 + 25 - 10x = ( x - 5)^2            b) -8y^3 + x^3= (x - 2)(x^2+2xy+x^2)

Answer 8

x^{2 _} 2.5.x +5²

 

Answer 9

 

Answer 10

a)x²+25-10x

=(x+5)²

b)-8y³+x³

=(-2y+x)(4y²+2xy+x³)

 

 

Answer 11

a) ( x - 5 )²

b) ( x - 2y ).( x²  + 2xy +  4y²)

Answer 12

a)x²+25-10x

=(x+5)²

b)-8y³+x³

=(-2y+x)(4y²+2xy+x³)

 

 

Answer 13

a) �2+25−10�=�2−2.5.�+52=(�−5)2x2+25−10x=x2−2.5.x+52=(x−5)2

b) −8�3+�3=�3−(2�)3=(�−2�)(�2+2��+4�2)−8y3+x3=x3−(2y)3=(x−2y)(x2+2xy+4y2).

Answer 14

Answer 15

) �2+25−10�=�2−2.5.�+52=(�−5)2x2+25−10x=x²2−2.5.x+5²2=(x−5)²2

b) −8�3+�3=�3−(2�)3=(�−2�)(�2+2��+4�2)−8y3+x3=x³3−(2y)³3=(x−2y)(x²2+2xy+4y²2)

Answer 16

Answer 17

Answer 18

Answer 19

Answer 20

 

Answer 21

 

Answer 22

 

Answer 23

 

Answer 24

 

Answer 25

 

Answer 26

 

Answer 27

a)x^2+25-10x=(x-5)^2

b)-8y^3+x^3=(x-2y)(x^2+2xy+4y^2)

Answer 28

Drr

Answer 29

 

Answer 30

.