Rút gọn biểu thức
(5x+1)(x^2-1)-(2x-3)(4x^2-6x+9)
Rút gọn biểu thức
A = (1-2x)(4x2+2x+1)+8(x-1)(x2+x+1)
B = (5x+5)2+10(x-3)(1+x)+x2-6x+9
Bài 1: Rút gọn các biểu thức sau:
a, A = (x-2).(2x-1) - 2x (x+3)
b, B = (3x-2).(2x+1) - (6x-1).(x+2)
c, C = 6x.(2x+3) - (4x-1).(3x-2)
d, D = (2x+3).(5x-2)+(x+4).(2x-1) - 6x.(2x-3)
Bài 2: Chứng tỏ rằng các đa thức không phụ thuộc vào biến.
a, 2x(3x-5).(x+11) - 3x.(2x+3).(x+7)
b, (x2+5x-6).(x-1) - (x+2).(x2-x+1) - x(3x-10)
c, (x2+x+1).(x-1) - x2(x+1) + x2 - 5
Bài 1
A= (x-2)(2x-1)-2x(x+3)=2x2-x-4x+2-2x2-6x=-11x+2
Bài 1:
a) \(A=\left(x-2\right)\left(2x-1\right)-2x\left(x+3\right)\)
\(A=2x^2-x-4x+2-2x^2-6x\)
\(A=-11x+2\)
b) \(B=\left(3x-2\right)\left(2x+1\right)-\left(6x-1\right)\left(x+2\right)\)
\(B=6x^2+3x-4x-2-6x^2-12x+x+2\)
\(B=-12x\)
c) \(C=6x\left(2x+3\right)-\left(4x-1\right)\left(3x-2\right)\)
\(C=12x^2+18x-12x^2+8x+3x-2\)
\(C=29x-2\)
d) \(D=\left(2x+3\right)\left(5x-2\right)+\left(x+4\right)\left(2x-1\right)-6x\left(2x-3\right)\)
\(D=10x^2-4x+15x-6+2x^2-x+8x-4-12x^2+18x\)
\(D=36x-10\)
Bài 2:
a: Ta có: \(2x\left(3x-5\right)\left(x+11\right)-3x\left(2x+3\right)\left(x+7\right)\)
\(=2x\left(3x^2+33x-5x-55\right)-3x\left(2x^2+14x+3x+21\right)\)
\(=6x^3+56x^2-110x-6x^2-51x^2-63x\)
\(=-117x\)
b: Ta có: \(\left(x^2+5x-6\right)\left(x-1\right)-\left(x+2\right)\left(x^2-x+1\right)-x\left(3x-10\right)\)
\(=x^3+4x^2-11x+6-\left(x^3-x^2+x+2x^2-2x+2\right)-3x^2+10x\)
\(=x^3+x^2-x+6-x^3-x^2+x-2\)
=4
c: Ta có: \(\left(x^2+x+1\right)\left(x-1\right)-x^2\left(x+1\right)+x^2-5\)
\(=x^3-1-x^3-x^2+x^2-5\)
=-6
Rút gọn các biểu thức sau:
1. (6x+1)2 + (6x-1)2 - 2(1+6x)(6x-1)
2. 3x(x-2) - 5x(1-x) - 5(x2 - 3)
3. (7x-3)(2x+1) - (5x - 2)(x+4) - 9x2 + 17x
4. (6x -5)(x+8) - (3x-1)(2x+3) - 9(4x-3)
Tao không biết
Lưu lê thanh hạ rảnh lên à bạn ???
\(\left(6x+1\right)^2-2\left(6x+1\right)\left(6x-1\right)+\left(6x-1\right)^2\)
\(=\left(6x+1+6x-1\right)^2\)
\(=36x^2\)
\(3x\left(x-3\right)-5x\left(1-x\right)-5\left(x^2-3\right)\)
\(3x\left(x-3\right)-5\left(x-x^2+x^2-3\right)\)
\(3x\left(x-3\right)-5\left(x-3\right)\)
\(\left(x-3\right)\left(3x-5\right)\)
Rút gọn biểu thức
A= -(3x+7)+(5x-2)+(2x-10)
B= (6x+8)-(4x-5)-3x
C= 2.(5x+3)-(2x-1)+12
D=(x+7)-3.(x+1)+2x-5
A=-(3x+7)+(5x-2)+(2x-10)
=-3x-7+5x-2+2x-10
=(-3x+5x+2x)-(7+2+10)
=4x-19
B = (6x+8)-(4x-5)-3x
= 6x+8-4x+5-3x
= (6x-4x-3x) + (8+5)
= -x + 13
= 13-x
C = 2(5x+3) - (2x-1) + 12
= 10x+6 - 2x + 1 + 12
= (10x-2x) + (6+1+12)
= 8x + 19
D = (x+7)-3(x+1)+2x-5
= x+7-3x-3+2x-5
= (x-3x+2x) + (7-3-5)
= -1
Rút gọn biểu thức: A=(2x+3) (4x^2-6x+9) - 2(4x^2-1)
\(A=\left(2x+3\right)\left(4x^2-6x+9\right)-2\left(4x^2-1\right)\)
\(=8x^3-12x^2+18x+12x^2-18x+27-8x^2+2\)
\(=8x^3-8x^2+29\)
ta có
\(A=\left(2x+3\right)\left(4x^2-6x+9\right)-2\left(4x^2-1\right)\)
\(A=8x^3-12x^2+18x+12x^2-18x+27-8x^2+2\)
\(A=8x^3-8x^2+29\)
Trả lời:
A = ( 2x + 3 ) ( 4x2 - 6x + 9 ) - 2 ( 4x2 - 1 )
= 8x3 - 12x2 + 18x + 12x2 - 18x + 27 - 8x2 + 2
= 8x3 - 8x2 + 29
Rút gọn các biểu thức sau:
a) (4x-3 )(3x+2 )- (6x+1)(2x-5) +1
b) (3x+4)2+(4x-1)2+(2+5x)(2-5x)
c) (2x+1)(4x22x+1)+(2-3x)(4+6x+9x2)-9
Làm nhanh cả lời giải hộ mình nhé ! ><
a, (4x-3)(3x+2)-(6x+1)(2x-5)+1
=12x2-8x-9x+6-12x2+30x-2x+5+1
=11x+12
b, (3x+4)2+(4x-1)2+(2+5x)(2-5x)
=9x2+24x+16+16x2-8x+1+4-25x2
=16x+21
c, (2x+1)(4x22x+1)+(2-3x)(4+6x+9x2)-9
=8x3+1+8-27x3-9
=-19x3
swingrock có thể giải thik rõ hơn đc ko ạ
rút gọn biểu thức
A=(2x-3)(4x^2-6x+9)-2(4x^3-1)
\(A=\left(2x-3\right)\left(4x^2-6x+9\right)-2\left(4x^3-1\right)\)
\(A=8x^3-12x^2+18x-12x^2+18x-27-8x^3+2\)
\(A=\left(8x^3-8x^3\right)+\left(-12x^2-12x^2\right)+\left(18x+18x\right)+\left(-27+2\right)\)
\(A=-24x^2+36x-25\)
Bài 1: Rút gọn biểu thức
a. (6x+1).(x+2) - 2x.(3x-5)
b.(2x-1)2 - (2x-3).(2x+3)
c. (2x-3)3 - (3x+1) . (5-4x) - 16x2
d. (3x+2) - (x-5)- - x(3x - 13)
e. (5x+1).(x-2)-x.(5x-9)
g. x(x+3)2 -(x+2).(x2 - 2x+7) - 6x2
\(a,\left(6x+1\right)\left(x+2\right)-2x\left(3x-5\right)\)
\(=6x^2+12x+x+2-6x^2+10x\)
\(=23x+2\)
a) (6x + 1)(x + 2) - 2x(3x - 5)
= 6x2 + 12x + x + 2 - 6x2 + 10x
= (6x2 - 6x2) + (12x + x + 10x) + 2
= 23x + 2
b) (2x - 1)2 - (2x - 3)(2x + 3)
= 4x2 - 4x + 1 - 4x2 + 9
= (4x2 - 4x2) - 4x + (1 + 9)
= -4x + 10
c) (2x - 3)3 - (3x + 1)(5 - 4x) - 16x2
= 8x3 - 36x2 + 54x - 15x + 12x2 - 5 + 4x - 16x2
= 8x3 - (36x2 - 12x2 + 16x2) + (54x - 15x + 4x) - 5
= 8x3 - 40x2 + 43x - 5
d) (3x + 2) - (x - 5) - x(3x - 13)
= 3x + 2 - x + 5 - 3x2 + 13x
= (3x - x + 13x) + (2 + 5) - 3x2
= 15x + 7 - 3x2
\(e,\left(5x+1\right)\left(x-2\right)-x\left(5x-9\right)\)
\(=5x^2-10x+x-2-5x^2+9x\)
\(=-2\)
Kết quả rút gọn biểu thức (2x - 3) (4x^2 + 6x + 9) - 2 ( 4x^3 - 25) là x =