pt <=> \(8x^3+27-\left(8x^3-12x^2+6x-1\right)=\left(x^3+12x^2+48x+64\right)-\left(x^3-8\right)\)
<=> \(8x^3+27-8x^3+12x^2-6x+1=x^3+12x^2+48x+64-x^3+8\)
<=> \(12x^2-6x+28=12x^2+48x+72\)
<=> \(54x+44=0\)
<=> \(x=-\frac{22}{27}\)
pt <=> \(8x^3+27-\left(8x^3-12x^2+6x-1\right)=\left(x^3+12x^2+48x+64\right)-\left(x^3-8\right)\)
<=> \(8x^3+27-8x^3+12x^2-6x+1=x^3+12x^2+48x+64-x^3+8\)
<=> \(12x^2-6x+28=12x^2+48x+72\)
<=> \(54x+44=0\)
<=> \(x=-\frac{22}{27}\)
Tìm đkxđ của: 1, 3x/ 4x-8 2, 2x/ x²-9 3, 6/x³+1 4, 6x²/x²-2x+1 5, x-2/x²+3 6, 2x/x²+3+2
tìm x
a)(x+6)^2-x(x+9)=0
b)6x(2x+5)-(3x+4)(4x-3)=9
c)2x(8x+3)-(4x+1)=13
d)(x-4)^2-x(x+4)=0
e)(x-2)^2-(2x+3)(x-2)=0
làm phép chia :
a) (x^4 -2x^3 + 2x -1) : (x^2 - 1)
b) (x^3 -8) : (x^2 + 2x +4)
c) (x^6 - 2x^5 + 2x^4 + 6x^3 - 4x^2)n: 6x^2
d) (-2x^5 + 3x^2 - 4x^3) :2x^2
e) (15x^3 - 10x^2 + x - 2) : (x - 2)
f) (2x^4 - 3x^3 - 3x^2 + 6x - 2) : (x^2 - 2)
1) tìm x :
a) (x-3)(x+3)-(x+5)(x-1)=6
b)(3x-2)^2-(2x+1)^2-(5x-1)(x+1)=20
c)(2x+1)(4x^2-2x+1)+(3-2x)(9+6x+4x^2)+12x=4
2x ^3 -5x^2+4x-1) : (2x+1)
(x63 -2x+4) ; (x+2)
(6x^3 - 19x^2+23x-12):(2x-3)
(x^4 - 2 x ^3 - 1+ 2 x ):(x^2 - 1)
(6x^3 - 5x^2 + 4x -1 ) : (2x^2-x+1)
(x^4 -5x^2+4):(x^2-3x+2)
Tìm x, biết:
1) 2x . (x-5) -x . (2x-4) = 15
2) (x+1) . (x+2) - (x+4) . (x+3) = 6
3) 4x2 - 4x+5 - x . (4x-3) = 1-2x
4) (x+3) . (2x+1) - 2x2 = 4x-5
5) -4 . (2x-8) + (2x-1) . (4x+3) = 0
6) -3 . (x-2) + 4 . (2x-6) - 7 . (x-9)= 5 . (3-2)
7) (x-2) . (x+2) -2 . (x-4) = 10. 3x
8) 15x . (x-2) - (5x-1) . (3x + 1) = 6
9) (2x+4) . (x-3) - x . (2x-10) =15-20x
10) (4x-2) . (3x+4) - (2x-1) . (6x+5) = 100
HEPL ME !!! Cần làm gấp những bài này, ai lm dc mk tick cho ng đó nha !!! THANK YOU !!!!
B1: quy đồng mẫu số các phân thức:
a. 5/ 6x^2y ; 7/ 12xy^2 ; 11/ 18xy
b. 4x+2/ 15x^3y ; 5y - 3/ 9x^2y ; x+1/5xy^3
c. 3/2x ; 3x-3/2x-1 ; 3x-2/2x- 4x^2
d. x^3 + 2x / x^3+1 ; 2x/ x^2 - x +1 ; 1/ x+1
e. y/ 2x^2 - xy ; 4x/ y^2 - 2xy
f. 1/x+2 ; 3/ x^2 - 4 ; x-14/ ( x^2 + 4x + 4 ) (x-2)
g. 1/x+2 ; 1/ (x+2)(4x+7) ;
h. 1/x+3 ; 1/ (x+3)(x+2) ; 1/ (x+2)(4x+7)
B2: dùng quy tắc đổi dấu để tìm mẫu thức chung :
a.4/ x+2 ; 2/x-2 ; 5x-6/4-x^2
b. 1-3x/2x ; 3x-2/2x-1 ; 3x-2/2x-4x^2
c. 1/ x^2 + 6x + 9 ; 1/ 6x-x^2-9 ; x/ x^2 -9
d. x^2 + 2/ x^3 - 1 ; 2/ x^2 + x +1 ; 1/ 1-x
e. x/ - 2y ; x/ x+2y ; 4xy/ 4y^2 - x^2
Ai làm xong trước mình tick nha!
Bài 3 : Tìm x biết
a) (x-2)^2-x(x-3)=0
b) (x+3)(2x+1)-2(x-1)^2=0
c) (4x-5)^2=9(2-5x)^2
d) X^2-6x-13=0
e) (x+2)(x^2-2x+4)-x(x^2+2)=15
f) X^3-6x^2+12x-19=0
tìm x biết
a) (6x-3) (2x+4) + (4x-1) (5-3x) = -21
b) 6x (3x+5) - 2x (9x-2) + (17-x) (x-1) + x (x-18) =0
c) (15-2x) (4x+1) - (13-4x) (2x-3) - (x-1) (x+2) + x2=52
d) (8x-3) (3x+2) - (4x+7) (x+4) = (2x+1) (5x-1) - 33