\(=x+x^2-x^3+x^4+2+2x-2x^2+2x^3+\left(x-1\right)\left(x^3+x^2+x+1\right)\)
\(=x^4+x^3-x^2+3x+2+x^4-1\)
\(=2x^4+x^3-x^2+3x+1\)
\(=x+x^2-x^3+x^4+2+2x-2x^2+2x^3+\left(x-1\right)\left(x^3+x^2+x+1\right)\)
\(=x^4+x^3-x^2+3x+2+x^4-1\)
\(=2x^4+x^3-x^2+3x+1\)
Tìm x biết : (đề không sai)
1.\(-4x\left(x-7\right)+4x\left(x^2-5\right)\) \(=28x^2-13\)
2.\(\left(4x^2-5x\right)\left(3x+2\right)-7x\left(x-7\right)\)= \(\left(-4+x\right)\left(-2x+3\right)+12x^3+2x^2\)
3.\(\left(-4x^2-3\right)\left(2x+5\right)-\left(8x-3\right)\) \(\left(-x^2+2\right)=-5x^2\left(x-6\right)-3x^2-4\)
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.\(\left(-2x^2+5\right)\left(-x+3\right)-x^2\left(2x-6\right)\) \(=\left(x-1\right)\left(x+1\right)-\left(x-2\right)\left(x+4\right)\)
1.tìm x
a) \(\left(8-5x\right)\left(x+2\right)+4\left(x-2\right)\left(x+1\right)+2\left(x-2\right)\left(x+2\right)\)
b) \(4\left(x-1\right)\left(x+5\right)-\left(x+2\right)\left(x+5\right)=3\left(x-1\right)\left(x+2\right)\)
2. CMR
a) \(\left(x-y\right)\left(x^4+x^3y+x^2y^2+xy^3+y^4\right)=x^5-y^5\)
b)\(\left(x+y\right)\left(x^4-x^3y+x^2y^2-xy^3+y^4\right)=x^5+y^5\)
c)\(\left(x+a\right)\left(x+b\right)=x^2+\left(a+b\right)x+ab\)
giúp mik nha
chiều nay nộp r
Rút gọn biểu thức:
A=\(\text{4(x-1)(x+1)-5x(x-2)+x^2}\)
B=\(\left(y^2+2\right)\left(y-4\right)-\left(2y^2+1\right)\left(\dfrac{1}{2}y-2\right)\)
C=\(\left(3-2x\right)\left(x-2\right)-4\left(x-1\right)\left(x-3\right)-\left(x-2\right)\left(x+2\right)\)
\(^{3x^2\left(a^2+b^2\right)-3a^2b^2+3\left[x^2+\left(a+b\right)x+ab\right]\left[x\left(x-a\right)-b\left(x-a\right)\right]:2x^2=\dfrac{3}{2}x^2}\)
Tính giá trị
P=\(\left\{\left[ã-2\left(a+2\right)\right]\left[a\left(x-1\right)+2\right]+2\left(-a^2+4\right)3a^2.x\right\}:\left(-2ax\right)\)
Biết a=2 và x=1
Tìm \(x\) , biết:
a) \(\left(x+2\right)\left(x+3\right)-\left(x-2\right)\left(x+5\right)=6\)
b) \(\left(3x+2\right)\left(2x+9\right)-\left(x+2\right)\left(6x+1\right)=\left(x+1\right)-\left(x-6\right)\)
c) \(3\left(2x-1\right)\left(3x-1\right)-\left(2x-3\right)\left(9x-1\right)=0\)
CÁC BẠN LÀM NHANH GIÚP MIK NHA!
a\(8\left(x+\dfrac{1}{x}\right)^{2^{ }}+4\left(x^{2^{ }}+\dfrac{1}{x^2}\right)-4\left(x^2+\dfrac{1}{x^2}\right)\left(x+\dfrac{1}{x}\right)=\left(x+4\right)^2\)giải các phương trình\(\dfrac{x+4}{2x^2-5x+2}+\dfrac{x+1}{2x^2-7x+3}=\dfrac{2x+5}{2x^2-7x+3}\)
Giải phương trình:
a)\(\dfrac{1}{x+1}-\dfrac{5}{x-2}=\dfrac{15}{\left(x+1\right)\left(2-x\right)}\)
b) \(1+\dfrac{x}{3-x}=\dfrac{5x}{\left(x+2\right)\left(3-x\right)}+\dfrac{2}{x+2}\)
c)\(\dfrac{6}{x-1}-\dfrac{4}{x-3}=\dfrac{8}{\left(x-1\right)\left(3-x\right)}\)
d) \(\dfrac{x+2}{x-2}-\dfrac{1}{x}=\dfrac{2}{x\left(x-2\right)}\)
Câu 1: Tìm x:
a. \(\left(x-1\right)\left(x+2\right)-x^2+3=5\)
b. \(\left(2x+1\right)\left(x-3\right)-2x\left(x+7\right)=100\)
c. \(\left(3x-1\right)\left(x+2\right)-\left(2-3x\right)\left(x+3\right)=12\)
Câu 2: Chứng minh giá trị biểu thức sau không phụ thuộc vào biến
\(\left(x-5\right)\left(2x+3\right)-2x\left(x-3\right)+x+7\)
Tìm x biết :
a) \(x\left(x^2+x+1\right)-x^2\left(x-1\right)=2x+5\)
b)(x-3)(x-2)-(x+1)(x-5)=0
c)\(x\left(2x-1\right)\left(x+5\right)-\left(2x^2+1\right)\left(x+4,5\right)=3,5\)