6x+2+6x=1332
2.3x+1-3x=135
3x(3.2-1)=5
2.3x+1-3x=135
giải phương trình:
a, \(3^{3x}=2^{6x}-3.2^{3x}-13\)
b, \(\sqrt{2x^2-1}+\sqrt{x^2-3x-2}=\sqrt{2x^2+2x+3}+\sqrt{x^2-x+2}\)
Tính `M = ( (3x)/(1-3x) + (2x)/(3x+1) ) : (6x^2 +10x)/(1-6x+9x^2)`
ĐKXĐ: \(x\ne\left\{-\dfrac{1}{3};\dfrac{1}{3};0;-\dfrac{4}{3}\right\}\)
\(M=\left(\dfrac{3x\left(1+3x\right)}{\left(1-3x\right)\left(1+3x\right)}+\dfrac{2x\left(1-3x\right)}{\left(1-3x\right)\left(1+3x\right)}\right):\dfrac{2x\left(3x+5\right)}{\left(1-3x\right)^2}\)
\(=\left(\dfrac{x\left(3x+5\right)}{\left(1-3x\right)\left(1+3x\right)}\right).\dfrac{\left(1-3x\right)^2}{2x\left(3x+5\right)}\)
\(=\dfrac{1-3x}{2\left(1+3x\right)}\)
a) (\((\frac{3x}{1-3x}+\frac{2x}{3x+1}):\frac{6x^2+10x}{1-6x+9x^2}\)
\(\left(\dfrac{3x}{1-3x}+\dfrac{2x}{3x+1}\right):\dfrac{6x^2+10x}{1-6x+9x^2}\)
\(\left(\dfrac{3x}{1-3x}+\dfrac{2x}{3x+1}\right):\dfrac{6x^2+10x}{1-6x+9x^2}\)\(\left(ĐKXĐ:x\ne\pm\dfrac{1}{3}\right)\)
\(=\left[\dfrac{-3x\left(3x+1\right)+2x\left(3x-1\right)}{\left(3x-1\right)\left(3x+1\right)}\right]:\dfrac{2x\left(3x+5\right)}{\left(3x-1\right)^2}\)
\(=\dfrac{-9x^2-3x+6x^2-2x}{\left(3x-1\right)\left(3x+1\right)}.\dfrac{\left(3x-1\right)^2}{2x\left(3x+5\right)}\)
\(=\dfrac{-3x^2-5x}{\left(3x-1\right)\left(3x+1\right)}.\dfrac{\left(3x-1\right)^2}{2x\left(3x+5\right)}\)
\(=\dfrac{-x\left(3x+5\right).\left(3x-1\right)^2}{\left(3x-1\right)\left(3x+1\right).2x\left(3x+5\right)}\)
\(=\dfrac{1-3x}{2\left(3x+1\right)}\)
\(=\dfrac{1-3x}{6x+2}\)
A=x+6x^2+7x^2-6x+1
A=(x^2)^2+2x^2.3x+9x^2-1x^2-6x+7
A=(x^2+3x)^2-2.(x^2+3x).1+1
A=(x^2+3x)^2>=0 với mọi x khi x^2=3x-1=0
a,2(1-6x)=(8+2x)
b,1/3-2x/5=1/10+4x/7
c,1-3x/+1=5-6x/2
câu c là tử số là 1-3x và 5-6x
a: =>2-12x=8+2x
=>-14x=6
=>x=-3/7
b: \(\dfrac{1}{3}-\dfrac{2}{5}x=\dfrac{1}{10}+\dfrac{4}{7}x\)
=>-2/5x-4/7x=1/10-1/3
=>-14/35x-20/35x=3/30-10/30
=>-34/35x=-7/30
=>x=7/30:34/35=49/204
Tìm x:
1) -3.(1-2x) - 4.(1+3x) = -5x + 5
2) 3.(2x - 5) - 6.(1 - 4x) = -3x + 7
3) (1 - 3x) - 2.(3x - 6) = -4x - 5
4) x.(4x - 3) - 2x.(2x - 1) = 5x - 7
5) 3x.(2x - 1) - 6x.(x + 2) = -3x + 4
6) (1 - 2x).3 - 4.(6x - 1) = 7x - 5
7) 6x - 3.(1 - 4x) - 5.(x + 1) = 2x + 7
8) 6.(1 - 3x) - 3.(2x + 5) = -10x + 7
9) 3x.(1 - 2x) + 6x^2 - 7x = 8.(1 - 2x) - 9
10) 2x.(1 + 3x) - 3x.(4 + 2x) = 3x - 4
* Trả lời:
\(\left(1\right)\) \(-3\left(1-2x\right)-4\left(1+3x\right)=-5x+5\)
\(\Leftrightarrow-3+6x-4-12x=-5x+5\)
\(\Leftrightarrow6x-12x+5x=3+4+5\)
\(\Leftrightarrow x=12\)
\(\left(2\right)\) \(3\left(2x-5\right)-6\left(1-4x\right)=-3x+7\)
\(\Leftrightarrow6x-15-6+24x=-3x+7\)
\(\Leftrightarrow6x+24x+3x=15+6+7\)
\(\Leftrightarrow33x=28\)
\(\Leftrightarrow x=\dfrac{28}{33}\)
\(\left(3\right)\) \(\left(1-3x\right)-2\left(3x-6\right)=-4x-5\)
\(\Leftrightarrow1-3x-6x+12=-4x-5\)
\(\Leftrightarrow-3x-6x+4x=-1-12-5\)
\(\Leftrightarrow-5x=-18\)
\(\Leftrightarrow x=\dfrac{18}{5}\)
\(\left(4\right)\) \(x\left(4x-3\right)-2x\left(2x-1\right)=5x-7\)
\(\Leftrightarrow4x^2-3x-4x^2+2x=5x-7\)
\(\Leftrightarrow-x-5x=-7\)
\(\Leftrightarrow-6x=-7\)
\(\Leftrightarrow x=\dfrac{7}{6}\)
\(\left(5\right)\) \(3x\left(2x-1\right)-6x\left(x+2\right)=-3x+4\)
\(\Leftrightarrow6x^2-3x-6x^2-12x=-3x+4\)
\(\Leftrightarrow-15x+3x=4\)
\(\Leftrightarrow-12x=4\)
\(\Leftrightarrow x=-\dfrac{1}{3}\)
GIẢI CÁC PHƯƠNG TRÌNH SAU:
2x3+6x2+6x+1=0
X^3-3X^2+3X-3=0
2X^3+6X^2+6X+1=0
3X^3+18X^2+36X+23=0
1 thinh nhan
a(3x-x)(4x-5)-(4x-1)(3x-2)
b2x(6x-2)-3x(4x-1)
2dung dinh nghia phan thuc bang nhau ,chung minh
a)12x^2y/8xy=6x^2y^2/4xy^2
b)2(x-1)/6x=x^2-x/3x^2
Thực hiện phép tính (1/1-3x) : 6x^2-6x/1-6x+9x^2
em mới học lớp 3 tuổi chưa bít nên chị cứ k cho em
CHỊU TỚ CHƯA HỌC