phan tich da thuc thanh nhan tu bang pp dung hang dang thuc:
a) 16x^2 - (x^2 + 4)^2
b) 27x^3 - 54x^2 + 36x - 8
c) (x+y)^3 - (x-y)^3
help me
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 thanh nhan tu bang pp dung hang dang thuc 1+8x^6y^3
phan tich da thuc thanh nhan tu bang cach them bot cung 1 hang tu
:\(x^3+x^2+4\)
\(x^3+x^2+4\)
\(=x^3-x^2+2x^2+2x-2x+4\)
\(=\left(x^3-x^2+2x\right)+\left(2x^2-2x+4\right)\)
\(=x\left(x^2-x+2\right)+2\left(x^2-x+2\right)\)
\(=\left(x^2-x+2\right)\left(x+2\right)\)
x3 + x2 + 4
= x3+ x2 + 4 + 43 - 43
= (x + 4)3 - 43
= [(x+ 4 - 4)] [(x+4)2+ (x+4).4 + 42]
#) TL :
x3 + x2 + 4
= x3 - x2 + 2x2 + 2x - 2x + 4
= x( x2 - x + 2 ) + 2( x2 - x + 2 )
= ( x + 2 )( x2- x + 2 )
Chúc bn hok tốt ạ ;3
Phan tich da thuc thanh nhan tu:
a)27x^3-27x^2+18x-4
b)2x^3-x^2-x-2
c)(x^2-3)^2+16
(x2 - 3)2 + 16
= (x2 - 3)2 + 42
= (x2 - 3 + 4)(x2 - 3 - 4)
= (x2 + 1)(x2 - 7)
a) 27x3-27x2+18x-4
=27x3-9x2-18x2+6x+12x-4
=9x2(3x-1)-6x(3x-1)+4(3x-1)
=(9x2-6x+4)(3x-1)
b) mk k bít lm
c)(x2-3)2+16
=(x2-3)2+42
=(x2-3+4)(x2-3-4)
=(x2+1)(x2-7)
k mk nha
thanks
3.7: Su dung cac hang dang thuc de phan tich cac da thuc sau thanh nhan tu:
a) -y2 + 1/9
b) x4 - 256
c) 9 (x - 3)2 - 4 (x + 1)2
d) 25x2 - 1/81 x2y2
a) \(-y^2+\dfrac{1}{9}\)
\(=-\left(y^2-\left(\dfrac{1}{3}\right)^2\right)\)
\(=-\left(y+\dfrac{1}{3}\right)\left(y-\dfrac{1}{3}\right)\)
b) \(4^4-256\)
\(=4^4-4^4\)
\(=0\)
c) \(9\left(x-3\right)^2-4\left(x+1\right)^2\)
\(=\left(3x-9\right)^2-\left(2x+2\right)^2\)
\(=\left(3x-9+2x+2\right)\left(3x-9-2x-2\right)\)
\(=\left(5x-7\right)\left(x-11\right)\)
\(a,=\left(\dfrac{1}{3}-y\right)\left(\dfrac{1}{3}+y\right)\\ b,=\left(x^2-16\right)\left(x^2+16\right)\\ =\left(x-4\right)\left(x+4\right)\left(x^2+16\right)\\ c,=\left[3\left(x-3\right)-2\left(x+1\right)\right]\left[3\left(x-3\right)+2\left(x+1\right)\right]\\ =\left(3x-9-2x-2\right)\left(3x-9+2x+2\right)\\ =\left(x-11\right)\left(5x-7\right)\\ d,=\left(5x-\dfrac{1}{9}xy\right)\left(5x+\dfrac{1}{9}xy\right)=x^2\left(5-\dfrac{1}{9}y\right)\left(5+\dfrac{1}{9}y\right)\)
phan tich da thuc sau thanh nhan tu : x^4 - 6x^3 + 54x - 81
\(x^4-6x^3+54x-81\)
\(=x^4+3x^3-9x^3+27x^2-27x^2 +81x-27x-81\)
\(=\left(x^4+3x^3\right)-\left(9x^3+27x^2\right)+\left(27x^2+81x\right)-\left(27+81\right)\)
\(=x^3\left(x+3\right)-9x^2\left(x+3\right)+27x\left(x+3\right)-27\left(x+3\right)\)
\(=\left(x+3\right)\left(x^3-9x^2+27x-27\right)\)
\(=\left(x+3\right)\left(x-3\right)^3\)
phan tich da thuc thanh nhan tu
a) m^2 -7m +12
b) 2x^4 -x^3 -54x +27
A, m2-7m+12=m2-3m+12-4m=m(m-3)-4(m-3)=(m-4)(m-3)
B, 2x4-x3+27-54x=x3(2-x)-27(2-x)=(x3-27)(2-x)=(x-3)(x2+3x+9)(2-x)
a) m^2 -7m +12 = m^2 -3m -4m +12
=m(m -3)-4 (m- 3)
=(m-4)(m-3)
b) 2x^4-x^3 -54x+ 27
=(2m^4-x^3)- (54x - 27)
=x^3(2x-1)-27(2x-1)
=(x^3-27)(2x-1)
Phan tich da thuc thanh nhan tu
\(\left(xy+4\right)^2-4\left(x+y\right)^2\)
\(x^4-4x^3+8x^2-16x+16\)
Phan tich thanh nhan tu bang ki thuat no sung hang dang thuc.
3x^2+8xy-3y^2
x^2 - x - xy - 2y^2+2y
x^2+2y^2-3xy + x -2y
x^2+x-xy-2y^2+y