PTĐTTNT`3x-3y+2x^2-2y^2`
PTĐTTNT:
`3x^2y-12x^3y^2`
`2x^2(x-y)-4xy(x-y)`
\(3x^2y-12x^3y^2=3x^2y\left(1-4xy\right)\)
\(2x^2\left(x-y\right)-4xy\left(x-y\right)\)
\(=2x\left(x-y\right)\left(x-2y\right)\)
ptđttnt : a, 9x^2y^3- 3x^4y^2- 6x^3y^2 + 18xy^4
b,7x^2y^2 - 21xy62z + 7xyz - 14xy
c,a^3x^2y - 5/2a63x^4 + 3/2a^4x^2y
1) \(x^2-2x+1+x^2y-xy=\left(x-1\right)^2+xy\left(x-1\right)=\left(x-1\right)\left(x+xy-1\right)\)
2) \(x^2+6x+9+x^2y+3xy\)
\(=\left(x+3\right)^2+xy\left(x+3\right)\)
\(=\left(x+3\right)\left(x+xy+3\right)\)
(2x+3y)^2+(3x-2y)^2-2(2x+3y)(3x-2y)
\(\left(2x+3y\right)^2+\left(3x-2y\right)^2-2.\left(2x+3y\right).\left(3x-2y\right)\)
\(=\left(2x+3y\right)^2-2.\left(2x+3y\right).\left(3x-2y\right)+\left(3x-2y\right)^2\)
\(=[\left(2x+3y\right)-\left(3x-2y\right)]^2\)
\(=\left(2x+3y-3x+2y\right)^2\)
\(=\left(5y-x\right)^2\)
1. Rút gọn: P= (x-y)^2+(x+y)^2-2(x+y)(x-y)-4x^2
2. PTĐTTNT: a) x^3-x^2y+3x-3y
b) x^3-2x^2-4xy^2+x
c) (x+2)(x+3)(x+4)(x+5)-8
Help meeee !!!!!!
em ko lam dc anh ehh
em chua gap bai nao nhu the nay. noi dung hon la chua den lop lam haha
C=3x^2y-2xy^2+x^3y^3+3xy^2-2^2y-2x^3y^3
D=15x^2y^3+7y^2-8x^3y^2-12x^2+11x^3y^2-12x^2y^3
E=3x^5+1/3xy^4+3/4x^2y^3-1/2x^5y+2xy^4-x^2y^3
tìm bậc
PTĐTTNT
a, 2x^y - 8x^2y + 8xy
b, 4x + 8xy - 3x-6y
c, xy^2 - 4xy + 4y^2 - 9
d, 2x^2 + 2x - 24
Giúp mình vs nhé !
Tìm x
a/ 8x^2-(2x+5)(4x-2)-9=0
PTĐTTNT
1/ 5x^2-10-x+2
2/ 3x^2-6xy-3y^2-12z^2
3/ x^2-3x+2
Tìm x:
\(8x^2-\left(2x+5\right)\left(4x-2\right)-9=0\)
\(\Leftrightarrow8x^2-\left(8x^2-4x+20x-10\right)-9=0\)
\(\Leftrightarrow8x^2-8x^2+4x-20x+10-9=0\)
\(\Leftrightarrow-16x+1=0\)
\(\Leftrightarrow-16x=-1\)
\(\Leftrightarrow x=\dfrac{-1}{-16}=\dfrac{1}{16}\)
Vậy \(x=\dfrac{1}{16}\)
Bài 1:
\(a,8x^2-\left(2x+5\right)\left(4x-2\right)-9=0\)
\(\Rightarrow8x^2-\left(8x^2+16x-10\right)-9=0\)
\(\Rightarrow8x^2-8x^2-16x+10-9=0\)
\(\Rightarrow-16x+1=0\)
\(\Rightarrow x=\dfrac{1}{16}\)
Tìm x:
a) 8x2 - (2x + 5)(4x - 2) - 9 =0
8x2 - (8x2 - 4x + 20x - 10) - 9= 0
8x2 - (8x2 + 16x - 10) - 9 =0
8x2 - 8x2 - 16x + 10 - 9 = 0
- 16x + 1 =0
- 16x = - 1
x = \(\frac{1}{16}\)
Vậy \(x = \frac{1}{16}\)
PTĐTTNT:
3/ x2 - 3x + 2
= x2 - x - 2x + 2
= x(x - 1) - 2(x - 1)
= (x - 1)(x - 2)
pn coi lại câu 1 và 2 nhé
cho x, y >0 . cmr (2x^2+3y^2)/(2x^3+3y^3)+(2y^2+3x^2)/(2y^3+3x^3)<=4/x+y