a, x(2x - 3) - 2x(x + 2) = 20
= 2x^2 - 3x - 2x^2 - 4x = 20
= -7x = 20
=> x = -20/7
a, x(2x - 3) - 2x(x + 2) = 20
= 2x^2 - 3x - 2x^2 - 4x = 20
= -7x = 20
=> x = -20/7
Tìm x:
a) (x-20) mũ 2 -(x+1)(x+3)=-7
b) (3x+5)(4-3x)=0
c) x mũ 3 -9x=0
d)2/3x (x mũ 2 -4)=0
e) (2x+1)-x(2x+1)=0
f)(2x-1) mũ 2 -(2x+5) (2x-5) =18
g)x mũ 2 -25 =6x-9
Đề: Tìm x
a)2x.(3x+5)-x.(6x-1)=33 k)5(x+3)-2x(x+3)=0
b)x(3x-1)+12x-4=0 i)5x(x-2)-(2-x)=0
c)5x(2x+1)-12x-6=0 m)x(x-1)-2(1-x)=0
d)x3-5x2+4x-20=0
e)2x3-5x2+2x-5=0
g)(x-2)3-x(x+1).(x-1)+62=5
Phan tich da thuc thanh nhan tu :
a, -x^3 * ( 2x + 1 )^2 + 49x
b, 125x^2 + 20y - 5y^2 - 20
c, ( 1+ 2x )*(1 - 2x ) - x*(x + 2 )*( x - 2 )
d, ( x - z )*(x + z) - y*(2x - y )
e, x^2 - 3x - 54
Giup minh voi nhe cac ban. Minh se tick cho.
Tìm x :
a, (2x-5).(x+2)-2x.(x-1)=15
b, (5-2x).(2x+7)=4\(x^2\)-25
c, x.(4x-5)-(2x+1)\(^2\)=0
M.n giúp em với
20 Rút gọn
a) (2x-y)(2x+y)-(2x+y)^2 ; b) (x-3)(x^2+3x+9)-(5-x)^2
c) (2x+y)(4x^2-2xy+y^2)-(2x+y)^3 ; d) (3x-5)^2-(3x+5)^2
Bài 2. Cho biểu thức: M = (2x + 3)(2x - 3) – 2(x + 5)2 – 2(x - 1)(x + 2)
a) Rút gọn M.
b) Tính giá trị của M tại x =
c) Tìm x để M = 0.
1. Thu gọn:
a) (3x-1). (x-2) + (x-1). (x+1)
b) (4x-3). (2x-5) - (8x-2). (x-1)
2. Tìm x:
a) 3x. (x-3) - x. (3x-2) = 2
b) -2x. (x+1) - 3. (1-x) + 2x2 = 3
c) (x-2). (x+2) + (3.x). (x+1) = 0
d) (2x-1). (x+3)- (x-2). (2x+1) = 10
Tìm x biết:
a)(x+3)^2+(x-2)(x+2)-2(x+1)=7
b)x(2x-1)-(x-2)(2x+3)=0
c)(x-1)(x+2)-x-2=0
d)x[(3x+2)+(x+1)^2-(2x-5)(2x+5)]=0
đ) 2x^2-7x+5=0
e) (2x+3)(x-5)=(2x+1)(2×+3)