a: \(\Leftrightarrow5x\left(x^2-6x+9\right)-5\left(x^3-3x^2+3x-1\right)+15\left(x^2-4\right)=5\)
\(\Leftrightarrow5x^3-30x^2+45x-5x^3+15x^2-15x+5+15x^2-20=5\)
\(\Leftrightarrow30x-15=5\)
hay x=2/3
b: \(\Leftrightarrow x^3+9x^2+27x+27-9x^3-6x^2-x+8x^3+1-3x^2=42\)
\(\Leftrightarrow26x+28=42\)
=>26x=14
hay x=7/13
Tìm x, biết :
a) 5x . (x - 3)2 - 5 . (x - 1)3 +15 . (x + 2) . (x - 2) = 5
b) (x + 3)3 - x . (3x + 1)2 + (2x +1) . (4x2 - 2x +1 ) - 3x2 = 42
Tìm x, biết :
a) 5x . (x - 3)2 - 5 . (x - 1)3 +15 . (x + 2) . (x - 2) = 5
b) (x + 3)3 - x . (3x + 1)2 + (2x +1) . (4x2 - 2x +1 ) - 3x2 = 42
Tìm x, biết :
a) 5x . (x - 3)2 - 5 . (x - 1)3 +15 . (x + 2) . (x - 2) = 5
b) (x + 3)3 - x . (3x + 1)2 + (2x +1) . (4x2 - 2x +1 ) - 3x2 = 42
Tìm x, biết:
a) (x + 2). (x2 - 2x + 4) - x. (x - 3). (x + 3) = 26
b) 6. (x + 1)2 + 2. (x - 1). (x2 + x +1) - 2. (x + 1)3 = 32
c) 5x. (x - 3)2 - 5. (x - 1)3 + 15. (x + 2). (x - 2) = 5
d) (x + 3)3 - x. (3x + 1)2 + (2x + 1). (4x2 - 2x + 1) - 3x2 = 42
Tìm x biết
1.(x+3)2-(x+2).(x-2)=4x+17
2.(2x+1)2-(4x-1).(x-3)-15=0
3.(2x+3).(x-1)+(2x-3).(1-x)=0
4.2(5x-8)-3(4x-5)=4(3x-4)+11
5.(3x-1).(2x-7)-(1-3x).(6x-5)=0
Rút gọn các biểu thức sau:
a) 2x(2x-1)^2-3x(x+3)-4x(x+1)
b)(3x+1) (3^2+1) (3^4+1).....(3^100+1)
c) 5x(x^2-x)-x^2(5x-5) -15
d) (x+5)^2 - 4x(2x+3)^2 - (2x-1) (x+3) (x-3)
Tìm x biết
1. 2(5x-8)-3(4x-5)=4(3x-4)+11
2. (2x+1)2-(4x-1).(x-3)-15=0
3. (3x-1).(2x-7)-(1-3x).(6x-5)=0
Rút gọn :
1. (2x-5)(3x+1)-(x-3)^2+(2x+5)^2-(3x+1)^3
2. (2x-1)(2x+1)-3x-2)(2x+3)-(x-1)^3+(2x+3)^3
3. (x-2)(x^2+2x+4)-(3x-2)^3+(3x-4)^2
4. (7x-1)(8x+2)-(2x-7)^2-(x-4)^3-(3x+1)^3
5. (5x-1)(5x+1)-(x+3)(x^2-3x+9)-(2x+4)^2-(3x-4)^2+(2x-5)^3
6. (4x-1)(x+2)-(2x+5)^2-(3x-7)^2+(2x+3)^3=(3x-1)^3
Bài 1: Khai triển hằng đẳng thức:
a, ( x - y + 2z )2
b, ( 2x-3 ). ( 2x+3 ) . ( 4x2+9 )
Bài 2: Rút gọn biểu thức:
a, ( 5x+2 ).( 2-5x ) - ( 3x+2 ).( 2x+5 )2
b, ( -2x-3 )2 + 2(2x+1).( 2x+5 ) + ( 2x+5 )2
