a: Sửa đề: (5-2x)(5+2x)+2x(x+3)=4-2x^2
=>25-4x^2+2x^2+6x=4-2x^2
=>6x+25=4
=>6x=-21
=>x=-7/2
b: (3x-2)(-2x)+5x^2=-x(x-3)
=>-6x^2+4x+5x^2=-x^2+3x
=>4x=3x
=>x=0
c: =>7-(4x^2-9)=x^2+8x+16
=>7-4x^2+9-x^2-8x-16=0
=>-5x^2-8x=0
=>5x^2+8x=0
=>x(5x+8)=0
=>x=0 hoặc x=-8/5
Tìm x:
a, 3.(2x-1).(3x-1)-(2x-3).(9x-1)-3=-3
b, (3x-1).(2x+7)-(x+1).(6x-5)=(x+2)-(x-5)
c, (6x-2)2+(5x-2)2-4.(3x-1).(5x-2)=0
d, (x+3)2-(x-4).(x+8)=1
e, 3.(x+2)2+(2x-1)2-7.(x+3).(x-3)=36
Bài 1 làm tính nhân
2x.(x^2-7x-3)
(-2x^3+y^2-7xy).4xy^2
(-5x^3).(2x^2+3x-5)
(2x^2-xy+y^2).(-3x^3)
(x^2-2x+3).(x-4)
(2x^3-3x-1).(5x+2)
Bài 2 Thực hiện phép tính
A,(2x+3y^2)
B, (5x-y)^2
C, (2x+y^2)^3
D, ( 3x^2-2y)^3
Tìm x, biết:
a) 3x(4x-3) - 2x(5-6x) = 0
b) 5(2x-3) + 4x(x-2) + 2x(3-2x) = 0
c) 3x(2-x) + 2x(x-1) = 5x(x+3)
d) 3x(x+1) - 5x(3-x) + 6(x2 + 2x + 3) = 0
1. (2x +3) (x- 5) +(X-4 ) + (x-5) ( x-2 0 = (3x -5) ( x-4)
2. (8x-3) (3x +2) - (4x+ 7) (x+4) = (2x + 1) (5x-1)
3. 2x^2 + (x -1) (x+1)= 5x (x+10
4. 4- ( x-1) (x+5) - (x+2) (x+5) = 3(x-1) (x+2)
Thực hiện các phép tính sau:
a) (x2 -1) (x2 + 2x)
b) (2x-1)(3x+2)(3-x)
c) (x+3)(x2 + 3x-5)
d) (x+1)(x2 - x+1)
e) (2x3 - 3x-1)(5x+2)
f) (x2 - 2x+3)(x-4)
g) (4x-1)(3x+1)-5x(x-3)-(x-4)(x-3)
h) (5x-2)(x+1)-3x(x2-x-3)-2x(x-5)(x-4)
Tìm x biết
a) (2x+3)(x–4)+(x–5)(x–2)=(2x+1)(x–4)
b)(8x–3)(3x+2)–(4x+7)(x+4)=(2x+1)(5x–1)
c) 2x^2+3(x–1)(x+1)=5x(x+1)
d) (8–5x)(x+2)+4(x–2)(x+1)+(x–2)(x+2)
e)4(x–1)(x+5)–(x+2)(x+5)=3(x–1)(x+2)
Rút gọn biểu thức
a) 3x² - 2x ( 5+ 1,5x ) + 10
b) ( x² - 2x + 3 ) ( x - 4 )
c) ( 5x + 2 ) ( 2x² - 3x - 1 )
d) ( 25x² + 10xy + 4y² ) ( 5x + 2y )
e) ( 5x³ - x² + 2x - 3 ) ( 4x² - x + 2 )
Rút gọn:
A=(2x-1)(x+3)-(x-2)(3x-4)+5x
B=5x(2x²-3x+1)-2x(x+1)(x-2)
C=(3x+2)(x-1)-2x(x+3)-2x+1
Giúp mk nha mk đang cần gấp
Thanks!
Bài 1: Thực hiện phép tính
a) (3x-1)(9x2+3x+1)-4x(x-5)
b) (7x+2)(3-4x)-(x+3)(x2-3x+9)
c) (4x+3)(4x-3)-(2-x)(4+2x+x2)
d) (3x-8)(-5x+6)-(4x+1)(3x-2)
e) (3x-6)4x-2x(3x+5)-4x2
f) (5x-6)(6x-5)-x(3x+10)
Bài 2 : Tính
a) x(x+3)-x2=6
b) 2x(x-5)+x(-2x-1)=6
c) x (x+5)-(x+1)(x-2)=7
d)(3x+4)(6x-3)-(2x+1)(9x-2)=10
