\(\Leftrightarrow x\cdot\dfrac{5}{2}-3x^2+15-18x+12x-2+\dfrac{1}{4}x+3=0\)
\(\Leftrightarrow-3x^2-\dfrac{13}{4}x+16=0\)
\(\Leftrightarrow-12x^2-13x+64=0\)
hay \(x\in\left\{1,83;-2,91\right\}\)
1) (x2-4x+16) (x+4)-x(x+1) (x+2)+3x2=0
2) (8x+2) (1-3x)+(6x-1) (4x-10)=-50
3) (x2+2x+4) (2-x)+x(x-3) (x+4)-x2+24=0
4) (\(\dfrac{x}{2}\)x2+3) (5-6x)+(12x-2) (\(\dfrac{x}{4}\)x4+3)=0
Tìm x, biết:
a) (2x+2)(x-1)-(x+2)(2x+1)=0;
b)(3x+1)(2x-3)-6x(x+2)=16;
c)(12x-5)(4x-1)+(3x-7)(1-16x)=81
mn ơi giúp mik vs ạ :<
Bài 1 : Tính
a) ( x + 1 ) \(^2\)+ ( x - 2 ) ( x + 3 ) - 4 x
b) ( 6x\(^5\)y\(^2\)-9x\(^4\)y\(3\)+ 12x\(^3\)y\(^4\)) : 3x\(^3\)y\(2\)
Tìm x
a) 3(2x-1)-5(x-3)+6(3x-4)=24
b) 6x²-(2x-3)(3x+2)-1=0
c) 4x²-12x=9
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: Tìm a, b, c biết
3x^2(a^2-2bx-3c)=3x^4-12x^3+27x2
Bài 2:Tìm x biết
a) 4(x+2)-7(2x-1)+3(3x-4)=30
b) 2(5x-8)-3(4x-5)=4(3x-4)+11
c) 5x(1-2x)-3x(x+18)=0
d) (x+2)(x+3)-(x-2)(x+5)=0
tìm x, biết:
a) 4x(1/2-3x)+1=5-12x^2
b) 3x(2x-1)-6x(3-x)=12
1. làm tính nhân
a) (x - y)(x2 + xy + y2)
b) (a3 - 2a2 + a - 1)(a - 5)
c) (x2 - 2x + y2)(x - y) - 3xy (y - x)
2. tìm x:
a. (12x - 5)(x + 1) + (6x - 2)(3 - 2x ) = 5
b. (x - 5)(2x + 3 ) - 2x( x - 3 ) + x + 7 = -8
XÁT ĐỊNH a,b,c BIẾT RẰNG:
a/\(-4x^{^{ }3}\cdot\left(ax^2+bx+c\right)=-8x^5+12x^4-20x^3\)
b/\(-2x^3\cdot\left(ax^2-bx-c\right)=-4x^5+6x^4+2x^3\)
