phan tich da thuc thanh nhan tu (x2-x+2)2+(x-2)
phan tich da thuc thanh nhan tu
x^2-x-y^2-y
x^2-2xy+y^2-z^2
bai 32 va 33 sbt
lop 8 bai phan tich da thuc thanh nhan tu bang cach nhom hang tu
Ta có
a, x2-x-y2-y
=x2-y2-(x+y)
=(x-y)(x+y) - (x+y)
=(x+y)(x-y-1)
b, x2-2xy+y2-z2
=(x-y)2-z2
=(x-y-z)(x-y+z)
con bai 32, 33 neu ban tra loi duoc minh h them
Phan tich da da thuc thanh nhan phan tu
(x^2+x+1)(x^2+x+2)-12
\(=\left(x^2+x\right)^2+3\left(x^2+x\right)+2-12\)
\(=\left(x^2+x\right)^2+3\left(x^2+x\right)-10\)
\(=\left(x^2+x+5\right)\left(x^2+x-2\right)\)
\(=\left(x^2+x+5\right)\left(x+2\right)\left(x-1\right)\)
phan tich da thuc thanh nhan tu(x^2+X)+3(x^2+x)+2
phan tich da thuc thanh nhan tu (x2-x+2)+(x-2)
\(=\left(x.x-x+2\right)+\left(x-2\right)\)
\(=x\left(x-x+2-2\right)=x.0\)
phan tich da thuc thanh nhan tu: x(x+2)(x^2+2x+2)+1
x(x+2)(x^2+2x+2)+1 = (x^2+2x)(x^2+2x+1)+1
Đặt x^2+2x+1=y ta được:
(y-)(y+1)+1=y^2-1+1=y^2
= (x^2+2x+1)^2
= ( x + 1 )^4
Phan tich da thuc thanh nhan tu x^2(1-x^2)-4-4x^2
phan tich da thuc thanh nhan tu (x^2-x+2)^2- 2x^2 +2x -7
Phan tich da thuc thanh nhan tu (1+2x)(1-2x)-x(x+2)(x-2)
\(\left(1+2x\right).\left(1-2x\right)-x.\left(x+2\right).\left(x-2\right)\))
\(=1-\left(2x\right)^2-x.x^2-2^2\)
\(=1-4x^2-x^3-4\)
Ko bt có đúng ko nữa
( 1 + 2x ) ( 1 - 2x ) - x ( x + 2 ) ( x - 2 )
= 1 - 4x2 - x ( x2 - 4 )
= 1 - 4x2 - x3 + 4x
= - ( x3 + 4x2 - 4x - 1 )
= - ( x3 - x2 + 5x2 - 5x + x - 1 )
= - [ x2 ( x - 1 ) + 5x ( x - 1 ) + ( x - 1 ) ]
= - ( x - 1 ) ( x2 + 5x + 1 )
(x^2+x)^2+4x^2+4x-12 phan tich da thuc thanh nhan tu
Phan tich da thuc thanh nhan tu :x^2+7x-15
x^2 + 7x -15
= x^2 + 7x +12,25 -27,25
= (x+3,5)^2 - 27, 25
= ( x+3,5 - \(\sqrt{27,25}\))(x+3,5+\(\sqrt{27,25}\))