I don't now
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I don't now
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Rút gọn:
a) \(\dfrac{3\left(x-y\right)\left(x-z\right)^2}{6\left(x-y\right)\left(x-z\right)}\)
b) \(\dfrac{6x^2y^2}{8xy^5}\)
c) \(\dfrac{3x\left(1-x\right)}{2\left(x-1\right)}\)
d) \(\dfrac{9-\left(x+5\right)^2}{x^2+4x+4}\)
e) \(\dfrac{x^2-2x+1}{x^2-1}\)
f) \(\dfrac{8x-4}{8x^3-1}\)
g) \(\dfrac{x^2+5x+6}{x^2+4x+4}\)
k) \(\dfrac{20x^2-45}{\left(2x+3\right)^2}\)
thực hiện phép tính:
a,\(\left(9x^2y^3-15x^4y^4\right):3x^2y-\left(2-3x^2y\right)y^2\)
b,\(\left(6x^2-xy\right):x+\left(2x^3y+3xy^2\right):xy-\left(2x-1\right)x\)
c,\(\left(x^2-xy\right):x-+\left(6x^2y^5-9x^3y^4+15x^4y^2\right):\dfrac{3}{2}x^2y^3\)
1.Cho x+y+z=0. CMR:
a) \(5\left(x^3+y^3+z^3\right)\left(x^2+y^2+z^2\right)=6\left(x^5+y^5+z^5\right)\)
b) \(x^7+y^7+z^7=7xyz\left(x^2y^2+y^2z^2+z^2x^2\right)\)
c) \(10\left(x^7+y^7+z^7\right)=7\left(x^2+y^2+z^2\right)\left(x^5+y^5+z^5\right)\)
d) \(2\left(x^5+y^5+z^5\right)=5xyz\left(x^2+y^2+z^2\right)\)
2. Tìm n∈ N để biểu thức sau là số nguyên tố
a) \(A=n^3-4n^2-4n-1\)
b) \(B=n^3-6n^2+9n-2\)
c) \(C=n^{1975}+n^{1973}+1\)
Câu 1: Rút gọn các biểu thức sau:
1. \(\left(x+y-z\right)^2+\left(y-z\right)^2+2z\left(z-y\right)\)
2. \(\left(3x+4\right)^2+\left(x-4\right)^2+2\left(3x+4\right)\left(x-4\right)\)
3.\(\left(3+1\right)\left(3^2+1\right)\left(3^4+1\right)\left(3^8+1\right)\left(3^{16}+1\right)\left(3^{32}+1\right)\)
4. \(2x\left(2x-1\right)^2-3x\left(x+3\right)\left(x-3\right)-4x\left(x+1\right)\)
5. \(\left(3+1\right)\left(3^2+1\right)\left(3^4+1\right)\left(3^8+1\right)\left(3^{16}+1\right)\left(3^{32}+1\right)\)
Câu 2: Tìm x
1. \(4\left(x+1\right)^2+\left(2x-1\right)^2-8\left(x-1\right)\left(x+1\right)=1\)
2. \(\left(3x+1\right)^2+\left(5x-2\right)^2=34\left(x+2\right)\left(x-2\right)\)
3. \(\left(x+3\right)^2+\left(x-2\right)^2=2x^2\)
4. \(4x^2-9-x\left(2x-3\right)=0\)
5. \(4x^2-12x+9=0\)
Câu 3: Tìm GTNN
D = \(\left(2x-1\right)^2+\left(x+2\right)^2\)
Câu 4: Cho \(a^2+b^2+c^2=ab+bc+ac\) . Chứng minh rằng a=b=c
giải phương trình
\(\left(x^2+x+1\right)\left(6-2x\right)\)
\(\left(8x-4\right)\left(x^2+2x+2\right)\)
\(\left(9x^2-1\right)=\left(3x+1\right)\left(2x-3\right)\)
\(2\left(9x^2+6x+1\right)=\left(3x+1\right)\left(x-2\right)\)
Bài 1:Tìm x
a) \(x^3+9x^2+27x+19=0\)
b) \(x\left(x+5\right)\left(x-5\right)-\left(x+2\right)\left(x^2-2x+4\right)=3\)
c) \(\left(5-2x\right)^2-16=x\)
d) \(\left(x-3\right)^3-\left(x-3\right)\left(x^2+3x+9\right)+9\left(x+1\right)^2=15\)
Bài 2:Tìm x,y,z
\(x^2+2x+y^2-6y+4z^2-4z+11=0\)
Rút gon biểu thức sau
a) \(\left(x-5\right)\left(2x+3\right)+2x\left(1-x\right)\)
b) \(\left(3x-5\right)^2-\left(x+5\right)\left(5-x\right)-\frac{5}{2}\left(-2x\right)^2\)
c) \(\left(3x+2\right)\left(4-6x+9x^2\right)-3x\left(3x-2\right)^2+12\left(-\frac{2}{3}-3x^2\right)\)
1, thực hiện các phép tính
a,\(\left(x+3y\right)\left(2x^2y-6xy^2\right)\)
b, \(\left(6x^5y^2-9x^4y^3+15x^3y^4\right):3x^3y^2\)
c, \(\left(2x+3\right)^2+\left(2x+5\right)^2-2\left(2x+3\right)\left(2x+5\right)\)
d, \(\left(y+3\right)^3-\left(3-y\right)^2-54y\)
Tìm x bt
1) \(3.\left(2x-1\right).\left(3x-1\right)-\left(2x-3\right).\left(9x-1\right)-3=-3\)\(-3\)
2) \(3x-1.\left(2x+7\right)-x+1.\left(6x-5\right)=x+2-\left(x-5\right)\)
3) \(3xy.\left(x+y\right)-\left(x+y\right).\left(x^2+y^2+2xy\right)+y^3=27\)
4) \(5.x+1.\left(1-x\right).\left(2x^2+3\right)=0\)
giúp mk vs mai mk đi hk rùi