rút gọn
(2x-8)(4x-3)-4x(2x-7)=-6x+4
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
Bài 1: Rút gọn
A = (3x - 1) ² + 2(3x -1) (2x+1) + (2x +1) ²
B = (2x +3) (4x ² - 6x + 9) + 8(1 - x) (1 +x +x ²)
A = \(\left(3x-1\right)^2+2\left(3x-1\right)\left(2x+1\right)+\left(2x+1\right)^2\)
A = \(\left(3x-1+2x+1\right)^2\)
A)
<=>(3x)^2−2×3x+1+2(3x−1)(2x+1)+(2x+1)^2
<=>(3x)^2−2×3x+1+(6x−2)(2x+1)+(2x+1)^2
<=>(3x)^2−2×3x+1+12x^2+6x−4x−2+(2x+1)^2
<=>(3x)^2−2×3x+1+12x^2+6x−4x−2+(2x)^2+2×2x+1
<=>32x^2−2×3x+1+12x^2+6x−4x−2+(2x)^2+2×2x+1
<=>9x^2−2×3x+1+12x^2+6x−4x−2+(2x)^2+2×2x+1
<=>9x^2−2×3x+1+12x^2+6x−4x−2+2^2x^2+2×2x+1
<=>9x^2−2×3x+1+12x^2+6x−4x−2+4x^2+2×2x+1
<=>9x^2−6x+1+12x^2+6x−4x−2+4x^2+2×2x+1
<=>9x^2−6x+1+12x^2+6x−4x−2+4x^2+4x+1
<=>(9x^2+12x^2+4x^2)+(−6x+6x−4x+4x)+(1−2+1)
<=> 25x^2
B)
<=>2x(4x^2−6x+9)+3(4x^2−6x+9)+8(1−x)(1+x+x^2)
<=>8x^3−12x^2+18x+3(4x^2−6x+9)+8(1−x)(1+x+x^2)
<=>8x^3−12x^2+18x+12x^2−18x+27+8(1−x)(1+x+x^2)
<=>8x^3−12x^2+18x+12x^2−18x+27+(8−8x)(1+x+x^2)
<=>8x^3−12x^2+18x+12x^2−18x+27+8(1+x+x^2)−8x(1+x+x^2)
<=>8x^3−12x^2+18x+12x^2−18x+27+8+8x+8x^2−8x(1+x+x^2)
<=>8x^3−12x^2+18x+12x^2−18x+27+8+8x+8x^2−(8x+8x2+8x^3)
<=>8x^3−12x^2+18x+12x^2−18x+27+8+8x+8x^2−8x−8x^2−8x^3
<=>(8x^3−8x^3)+(−12x^2+12x^2+8x^2−8x^2)+(18x−18x+8x−8x)+(27+8)
<=> 35
rút gọn
A= x^2-4x^2 -3 / x^4+6x-7
B= x^4+x^3 -x -1 / x^4+x^3+2x^2+x-1
Biểu thức rút gọn của biểu thức A = ( 2 x - 3 ) ( 4 + 6 x ) - ( 6 - 3 x ) ( 4 x - 2 ) là?
A. 0
B. 40x
C. - 40x
D. Kết quả khác.
Rút gọn lớp 8
(2x-3)(4x^2-6x+9)-8x(x^2-1)
= (8x^3 -27) -8x^3 +8x
= 8x-27
Bạn áp dụng hằng đẳng thức. Chúc bạn học tốt.
Rút gọn lớp 8
(2x-3)(4x^2-6x+9)-8x(x^2-1)
Kết quả rút gọn biểu thức (2x - 3) (4x^2 + 6x + 9) - 2 ( 4x^3 - 25) là x =
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 biểu thức
A=(2x-3)(4x^2-6x+9)-2(4x^3-1)
\(A=\left(2x-3\right)\left(4x^2-6x+9\right)-2\left(4x^3-1\right)\)
\(A=8x^3-12x^2+18x-12x^2+18x-27-8x^3+2\)
\(A=\left(8x^3-8x^3\right)+\left(-12x^2-12x^2\right)+\left(18x+18x\right)+\left(-27+2\right)\)
\(A=-24x^2+36x-25\)