TÌM X,BIẾT:
a/\(\left(5x+1^{ }\right)^2-\left(5x-3\right)\left(5x+3\right)=30\)
b/\(\left(x-1\right)\left(x^2+x+1\right)+x\left(x+2\right)\left(2-x\right)=5\)
BÀI 6 tìm x
1,\(2x\left(x-5\right)-\left(3x+2x^2\right)=0\) 2,\(x\left(5-2x\right)+2x\left(x-1\right)=13\)
3,\(2x^3\left(2x-3\right)-x^2\left(4x^2-6x+2\right)=0\) 4,\(5x\left(x-1\right)-\left(x+2\right)\left(5x-7\right)=6\)
5,\(6x^2-\left(2x-3\right)\left(3x+2\right)=1\) 6,\(2x\left(1-x\right)+5=9-2x^2\)
BT3: Tìm x
\(a,\left(x+2\right)^2-9=0\)
\(b,x^2-2x+1=25\)
\(c,\left(5x+1\right)^2-\left(5x-3\right)\left(5x+3\right)=30\)
\(d,\left(x-1\right)\left(x^2+x+1\right)+x\left(x+2\right)\left(2-x\right)=5\)
Tìm x biết :(đề không sai )
1.\(-4x\left(x-7\right)+4x\left(x^2-5\right)\) \(=28x^2-13\)
2.\(\left(4x^2-5x\right)\left(3x+2\right)-7x\left(x+5\right)\) \(=\left(-4+x\right)\left(-2x+3\right)+12x^3+2x^2\)
3.\(\left(-4x^2-3\right)\left(2x+5\right)\) \(-\left(8x-3\right)\left(-x^2+2\right)\) \(-5x\left(x-6\right)-3x^2-4\)
4.\(\left(x-7\right)\left(x+5\right)-\left(x-3\right)\left(x-2\right)\) \(=15x^2\left(x+1\right)-\left(3x^2-1\right)\) \(\left(5x^2-2\right)-21x^2\)
5.\(\left(x-3\right)\left(-x+10\right)+\left(x-8\right)\left(x+3\right)\)\(=\left(5x^2-1\right)\left(x+3\right)-5x^3-15x^2\)
6.\(\left(-2x^2+5\right)\left(-x+3\right)-x^2\left(2x-6\right)\) \(=\left(x-1\right)\left(x+1\right)-\left(x-2\right)\left(x+4\right)\)
Tìm \(x\):
\(8\)) \(1-\left(x-6\right)=4\left(2-2x\right)\)
\(9\))\(\left(3x-2\right)\left(x+5\right)=0\)
\(10\))\(\left(x+3\right)\left(x^2+2\right)=0\)
\(11\))\(\left(5x-1\right)\left(x^2-9\right)=0\)
\(12\))\(x\left(x-3\right)+3\left(x-3\right)=0\)
\(13\))\(x\left(x-5\right)-4x+20=0\)
\(14\))\(x^2+4x-5=0\)
Tìm x
\(2x.\left(x-5\right)-x.\left(3+2x\right)=26\)
\(\left(x-7\right).\left(x-5\right)-12.\left(3x-7\right)=15\)
\(4.\left(18-5x\right)-12.\left(3x-7\right)=15.\left(2x-16\right)-6.\left(x+14\right)\)
\(\left(x-1\right).\left(x^2+x+1\right)=x^3-2x\)
Tìm x biết
a, \(\left(5x-1\right)^2-\left(5x-4\right)\left(5x+4\right)=7\)
b,\(\left(4x-1\right)^2-\left(2x+3\right)^2+5\left(x+2\right)^2+3\left(x-2\right)\left(x+2\right)=500\)
Tìm x,
\(\left(x-3\right)\left(-2x+5\right)-2x\left(x-4\right)+\left(x-3\right)=\left(x-2\right)\left(x-1\right)-\left(x^2-5x\right)\)
Chứng minh biểu thức sau không phụ thuộc vào giá trị của biến:
A=\(^{x^2}-4x-x\left(x-4\right)-15\)
B=\(5x\left(x^2-x\right)-x^2\left(5x-5\right)-13\)
C=\(-3x\left(x-5\right)+3\left(x^2-4x\right)-3x+7\)
D=\(7\left(x^2-5x+3\right)-x\left(7x-35\right)-14\)
E=\(4x\left(x^2-7+2\right)-4\left(x^3-7x+2x-5\right)\)
H=\(x\left(5x-3\right)-x^2\left(x-1\right)+x\left(x^2-6x\right)-10+3x\)