\(\left|3x-1\right|-x=2\)
\(\Leftrightarrow\left[{}\begin{matrix}3x-1-x=2;x\ge\dfrac{1}{3}\\1-3x-x=2;x< \dfrac{1}{3}\end{matrix}\right.\) \(\Leftrightarrow\left[{}\begin{matrix}2x=3\\-4x=1\end{matrix}\right.\)
\(\Leftrightarrow\left[{}\begin{matrix}x=\dfrac{3}{2}\left(tm\right)\\x=-\dfrac{1}{4}\left(tm\right)\end{matrix}\right.\)
Vậy \(S=\left\{\dfrac{3}{2};-\dfrac{1}{4}\right\}\)
Rút gọn các biểu thức sau:
a,(3x+1)^2-2(3x+1)(3x-5)+(3x-5)^2
b,(3x^2-y)^2
c,(3x+5)^2+(3x-5)^2-(3x+2)(3x-2)
d,2x(2x-1)^2-3x(x+3)(Õ-3)-4x(x+1)^2
e,(x-2)(x^2+2x+4)-(x+1)^2+3(x-1)(x+1)
f,(x^4-5x^2+25)(x^2+5)-(2+x^2)^2+3(1+x^2)^2
tính
\(\dfrac{x^2+38x+4}{2x^2+17x+1}-\dfrac{3x^2-4x-2}{2x^2+17x+1}\)
\(\dfrac{3x+1}{3x^2-3x+1}+\dfrac{x^2-6x}{x^2-3x+1}\)
\(\dfrac{-x}{3x-2}+\dfrac{7x-4}{3x-2}\)
Rút gọn biểu thức:
a) (x 2 – 2x + 2)(x 2 – 2)(x 2 + 2x + 2)(x 2 + 2)
b) (x + 1)2 – (x – 1)2 + 3x 2 – 3x(x + 1)(x – 1)
c) (2x + 1)2 + 2(4x 2 – 1) + (2x – 1)2
d) (m + n)2 – (m – n)2 + (m – n)(m + n)
e) (3x + 1)2 – 2(3x + 1)(3x + 5) + (3x + 5)2
Tìm x :( bài 14 trang 11 sách bồi dưỡng năng lực tự học toán 8)
Câu 2 : (2x+3)2+(x-1)*(x+1)=5*(x+2)2-(x-5)*(x+1)+(x+4)2
Câu 3 : (-x+5)*(x-2)+(x-7)*(x+7)=(3x+1)2-(C)*(3x+2)
Câu 4 : (5x-1)*(x+1)-2(x-3)2=(x+2)*(3x-1)-(x+4)2+(x2-x)
Câu 5 : (4x-1)2-(3x+2)*(3x-2)=(7x-1)*(x+2)+(2x+1)2-(3x+2)
Câu 6 : (2x+3)2-(5x-4)*(5x+4)=(x+5)2-(3x-1)*(7x+2)-(x2-1+1)
Câu 7 : (1-3x)2-(x-2)*(9x+1)=(3x-4)*(3x+4)-9(x+3)2
Câu 8 : (3x+4)*(3x-4)-(2x+5)=(x-5)+(2x+1)2-(x2-2x)+(x-1)2
Câu 9 : (x-7)*(x+1)-(x-3)2=(3x-5)*(3x+5)-(3x+1)+(x-2)2-x2
Câu 10 : -5(x+3)2+(x-1)*(x+1)+(2x-3)=(5x-2)2-5x(5x+3)
Bài1:Rút gọn
a,(4x-5)(3x+2)-(7-3x)(x+2)
b,(-2x+1)(x-5)-3(x-2)(x+1)
c,(x^2-7)(x-5)+(3x^2+5)(2x-4)
d,(x^2+3x-2)(x+4)-4x(x-5)
Bài2:Tìm xbiết
a,(x-4)(x+3)-(x+1)(x-5)=8
b,(3x-2)(x+1)-3x(x+7)=13
c,(x+5)(x-5)-x(x+2)=9
d,(x-1)(x^2+x+1)-x(x^2-3)=1
Tính :
B=(x-3)3-(x+3).(x2-3x+9)+(3x-1).(3x+1)
C=(3x+2)3-18x.(3x+2)+(x-1)3-28x3+3x.(x-1)
(3x^2-16x) ÷ (-3x) +x(x-4) =-2 (5x^3+20x^2-25x) ÷25x=(x-1) (x+2) (3x+1) ^3=3x+1 x^2-4x+4=9(x-2) Tìm x
giúp mk giải với, gấp lắm
a) (x+10/(x-1)-(x-1)/(x+1)=(x^2+3x)/(X^2-1)
b) (x+2)/x=(x-1)/(x-2)
c) 1/(3x-1)+(2x+2)/(x-1)-(3x^2+1)/(3x^2-4x+1)=1
Giải phương trình:
a) 5 + 96/x2-16 = 2x-1/x+4 - 3x-1/4-x
b) 3x+2/3x-2 - 6/2+3x = 9x2/9x2-44
c) 1/x-1 + 1/x+1 = 2/x+2
d) x+1/x-2 - 5/x+2 = 12/x2-4 + 1
Thu gọn (x^2+3x+1)^2+(3x-1)-2*(x^2+3x+1)(3x-1)
