HV
2
K
Khách
Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
Các câu hỏi dưới đây có thể giống với câu hỏi trên
BC
9 tháng 7 2017
a) = x2 - 3x + 2x - 6
= x(x -3) + 2(x - 3)
= (x - 3)(x + 2)
b) = x2 - x + 5x - 5
= x(x - 1) + 5(x - 1)
= (x - 1)(x + 5)
c) = x3 - 5x2 + 5x2 - 25x + 6x - 30
= x2(x - 5) + 5x(x - 5) +6(x - 5)
= (x - 5)(x2 + 5x + 6)
= (x - 5)(x2 + 2x + 3x + 6)
= (x - 5)[x(x + 2) + 3(x + 2)]
= (x - 5)(x + 2)(x + 3)
9 tháng 7 2017
a) = x2 - 3x + 2x - 6
= x(x -3) + 2(x - 3)
= (x - 3)(x + 2)
b) = x2 - x + 5x - 5
= x(x - 1) + 5(x - 1)
= (x - 1)(x + 5)
c) = x3 - 5x2 + 5x2 - 25x + 6x - 30
= x2(x - 5) + 5x(x - 5) +6(x - 5)
= (x - 5)(x2 + 5x + 6)
= (x - 5)(x2 + 2x + 3x + 6)
= (x - 5)[x(x + 2) + 3(x + 2)]
= (x - 5)(x + 2)(x + 3)
24 tháng 8 2017
\(b.x^4+4x^2-5=x^4-x^2+5x^2-5\)
\(=x^2\left(x^2-1\right)+5\left(x^2-1\right)\)
\(=\left(x^2+5\right)\left(x^2-1\right)\)
\(=\left(x^2+5\right)\left(x-1\right)\left(x+1\right)\)
\(c.x^3-19x-30=x^3-25x+6x-30\)
\(=x\left(x-5\right)\left(x+5\right)+6\left(x-5\right)\)
\(=\left(x-5\right)\left(x^2+5x+6\right)\)
\(=\left(x-5\right)\left(x^2+2x+3x+6\right)\)
\(=\left(x-5\right)\left[x\left(x+2\right)+3\left(x+2\right)\right]\)
\(=\left(x-5\right)\left(x+2\right)\left(x+3\right)\)
KN
23 tháng 6 2019
a) \(x^2-x-6\)
\(=\left(x^2-3x\right)+\left(2x-6\right)\)
\(=x\left(x-3\right)+2\left(x-3\right)\)
\(=\left(x+2\right)\left(x-3\right)\)
23 tháng 6 2019
Mình nghĩ GP,SP là những cái điểm hỏi đáp
~ Học tốt ~
19 tháng 6 2016
a) \(x^2-x-2=x^2+x-2x-2=x\left(x+1\right)-2\left(x+1\right)\)
\(=\left(x+1\right)\left(x-2\right)\)
19 tháng 6 2016
a) \(x^2-x-2=x^2-2x+x-2=x\left(x-2\right)+\left(x-2\right)=\left(x-2\right)\left(x+1\right)\)
b) \(x^3-19x-30==x^3+2x^2-2x^2-4x-15x-30=x^2\left(x+2\right)-2x\left(x+2\right)-15\left(x+2\right)\)
\(=\left(x+2\right)\left(x^2+2x-15\right)=\left(x+2\right)\left(x-3\right)\left(x+5\right)\)
c) \(x^3-6x^2+11x-6=x^3-x^2-5x^2+5x+6x-6=x^2\left(x-1\right)-5x\left(x-1\right)+6\left(x-1\right)=\left(x-1\right)\left(x-2\right)\left(x-3\right)\)
LT
13 tháng 8 2020
Phân tích đa thức thành nhân tử:
a) a4 + a2 + 1
= a4 + 2a2 + 1 - a2
= (a2 + 1)2 - a2
= (a2 + 1 - a)(a2 + 1 + a)
b) a4 + a2 - 2
= a4 + 2a2 - a2 - 2
= a2(a2 + 2) - (a2 + 2)
= (a2 + 2)(a2 - 1)
= (a2 + 2)(a - 1)(a + 1)
c) x2 + 4x2 - 5
= 5x2 - 5
= 5(x2 - 1)
= 5(x - 1)(x + 1)
d) x3 - 19x - 30
= x3 - 25x + 6x - 30
= x(x2 - 25) + 6(x - 5)
= x(x - 5)(x + 5) + 6(x - 5)
= (x - 5)(x2 + 5x + 6)
= (x - 5)(x2 + 2x + 3x + 6)
= (x - 5)[x(x + 2) + 3(x + 2)]
= (x - 5)(x + 2)(x + 3)
e) x3 - 7x - 6
= x3 - 9x + 2x - 6
= x(x2 - 9) + 2(x - 3)
= x(x - 3)(x + 3) + 2(x - 3)
= (x - 3)(x2 + 3x + 2)
= (x - 3)(x2 + x + 2x + 2)
= (x - 3)[x(x + 1) + 2(x + 1)]
= (x - 3)(x + 1)(x + 2)
f) x3 - 5x2 - 14x
= x3 + 2x2 - 7x2 - 14x
= x2(x + 2) - 7x(x + 2)
= (x + 2)(x2 - 7x)
= x(x + 2)(x - 7)
13 tháng 8 2020
a) Ta có: \(a^4+a^2+1\)
\(=a^4+2a^2+1-a^2\)
\(=\left(a^2+1\right)^2-a^2\)
\(=\left(a^2-a+1\right)\left(a^2+a+1\right)\)
b) Ta có: \(a^4+a^2-2\)
\(=a^4-a^2+2a^2-2\)
\(=a^2\left(a^2-1\right)+2\left(a^2-1\right)\)
\(=\left(a^2-1\right)\left(a^2+2\right)\)
\(=\left(a-1\right)\left(a+1\right)\left(a^2+2\right)\)
c) Ta có: \(x^2+4x^2-5\)
\(=5x^2-5\)
\(=5\left(x^2-1\right)\)
\(=5\left(x-1\right)\left(x+1\right)\)
d) Ta có: \(x^3-19x-30\)
\(=x^3+2x^2-2x^2-4x-15x-30\)
\(=x^2\left(x+2\right)-2x\left(x+2\right)-15\left(x+2\right)\)
\(=\left(x+2\right)\left(x^2-2x-15\right)\)
\(=\left(x+2\right)\left(x^2-5x+3x-15\right)\)
\(=\left(x+2\right)\left[x\left(x-5\right)+3\left(x-5\right)\right]\)
\(=\left(x+2\right)\left(x-5\right)\left(x+3\right)\)
e) Ta có: \(x^3-7x-6\)
\(=x^3+2x^2-2x^2-4x-3x-6\)
\(=x^2\left(x+2\right)-2x\left(x+2\right)-3\left(x+2\right)\)
\(=\left(x+2\right)\left(x^2-2x-3\right)\)
\(=\left(x+2\right)\left(x^2-3x+x-3\right)\)
\(=\left(x+2\right)\left[x\left(x-3\right)+\left(x-3\right)\right]\)
\(=\left(x+2\right)\left(x-3\right)\left(x+1\right)\)
f) Ta có: \(x^3-5x^2-14x\)
\(=x\left(x^2-5x-14\right)\)
\(=x\left(x^2-7x+2x-14\right)\)
\(=x\left[x\left(x-7\right)+2\left(x-7\right)\right]\)
\(=x\left(x-7\right)\left(x+2\right)\)
28 tháng 10 2022
b: \(=x^3-25x+6x-30=\left(x-5\right)\left(x^2+5x+6\right)\)
\(=\left(x-5\right)\left(x+2\right)\left(x+3\right)\)
c: \(=x^3-x-6x-6=x\left(x-1\right)\left(x+1\right)-6\left(x+1\right)\)
\(=\left(x+1\right)\left(x^2-x-6\right)\)
\(=\left(x+1\right)\left(x-3\right)\left(x+2\right)\)
d: \(=x^4+4y^4+4x^2y^2-4x^2y^2\)
\(=\left(x^2+2y^2\right)^2-4x^2y^2\)
\(=\left(x^2-2xy+2y^2\right)\left(x^2+2xy+2y^2\right)\)
e: \(=\left(x^2+x\right)^2+3\left(x^2+x\right)-10\)
\(=\left(x^2+x+5\right)\left(x^2+x-2\right)\)
\(=\left(x^2+x+5\right)\left(x+2\right)\left(x-1\right)\)
15 tháng 4 2020
a)9(2x+1)2 - 4(x-1) 2
<=>33(2x+1)2-22(x+1)2
<=>(3(2x+1)) 2-(2(x+1))2
<=>(6x+3)2-(2x+1)2
<=>((6x+3)-(2x+1)) ((6x+3)+(2x+1))
<=>(6x+3-2x-1)(6x+3+2x+1)
<=.>(4x+2)(8x+4)
b) x3 - 19x- 30
<=>x3-25x+6x-30
<=.>x(x2-52)+6(x-5)
<=>x(x+5)(x-5)+6(x-5)
<=>(x-5) (x2+5x+6)
<=>(x-5) (x2+2x+3x+6)
<=>(x-5) ( x(x+2)+3(x+2))
<=>(x-5) (x+2)(x+3)
c) x4+ x2 +1
<=>x4+x2+1
<=>x4−x+x2+x+1
<=>x(x3−1)+(x2+x+1)
<=>x(x−1)(x2+x+1)+(x2+x+1)
<=>(x2+x+1)[x(x−1)+1]
<=>(x2+x+1)(x2−x+1)
câu d mình chịu :(((
NP
2
LP
1
9 tháng 8 2015
a) x3−19x−30=(x−5)(x+2)(x+3)
b) x4−x2+1=x4+2x2+1−3x2=(x2+1)2−(x√3)2=(x2+1+x√3)(x2+1−x√3)
\(a,x^2-x-6\)
\(=x^2+2x-3x-6\)
\(=x\cdot\left(x+2\right)-3\cdot\left(x+2\right)\)
\(=\left(x+2\right)\cdot\left(x-3\right)\)
b) x4 + 4x2 - 5
= [ ( x2 )2 + 2.2.x2 + 4 ] - 9
= ( x2 + 2 )2 - 32
= ( x2 + 2 - 3 )( x2 + 2 + 3 )
= ( x2 - 1 )( x2 + 5 )
c) x3 - 19x - 30
= x3 - 9x - 10x - 30
= x.( x2 - 9 ) - 10.( x - 3 )
= x.( x - 3 ).( x + 3 ) - 10.( x - 3 )
= ( x - 3 ).[ x.( x - 3 ) - 10 ]
= ( x - 3 ).( x2 - 3x - 10 )
= ( x - 3 ).( x2 + 2x - 5x - 10 )
= ( x - 3 ). [ x.( x + 2 ) - 5.( x + 2 ) ]
= ( x - 3 )( x + 2 )( x - 5 )