Tìm x , biết :
a. \(\left(x-2\right)^3-\left(x-3\right)\left(x^2+3x+9\right)+6\left(x+1\right)^2=15\)
b. \(2x^3-50x=0\)
c.\(5x^2-4\left(x^2-2x+1\right)-5=0\)
d. \(x^3-x=0\)
e. \(27x^3-27x^2+9x-1=1\)
Tìm x:
a. \(\left(3x+4\right)\left(3x-4\right)-\left(2x+5\right)^2=\left(x-5\right)^2+\left(2x+1\right)^2-\left(x^2-2x\right)+\left(x-1\right)^2\)
b. \(-5\left(x+3\right)^2+\left(x-1\right)\left(x+1\right)+\left(2x-3\right)^2=\left(5x-2\right)^2-5x\left(5x+3\right)\)
1)rút gọn
a) (x+5)(\(x^2\) - 5x + 25) - \(\left(x+3\right)^3\) + (x-2)(\(x^2\) + 2x + 4) - \(\left(x-1\right)^3\)
b)\(\left(x+3y\right)^3+\left(3x+2y\right)\left(9x^2-6xy+4y^2\right)-\left(2y-3x\right)^3\)
c)\(\left(3x+y\right)^3-\left(5x-y\right)\left(25x^2+5xy+y^2\right)+\left(x+2y\right)^3\)
2)tìm x,biết
a)\(\left(x-1\right)^2-\left(x-2\right)\left(x+3\right)+\left(x+2\right)^3=\left(x-3\right)\left(x^2+3x+9\right)+6x\left(x+2\right)\)
Cảm ơn các bạn ^^
Tìm x biết:
\(\left(x-1\right)^3-\left(x+3\right)\left(x^2-3x+9\right)+3\left(x^2-4\right)=2\)
Tính :
a) \(\left(2+xy\right)^2\)
b) \(\left(5-3x\right)^2\)
c) \(\left(5-x^2\right)\left(5+x^2\right)\)
d) \(\left(5x-1\right)^3\)
e) \(\left(2x-y\right)\left(4x^2+2xy+y^2\right)\)
f) \(\left(x+3\right)\left(x^2-3x+9\right)\)
Chứng minh giá trị của các biểu thức không phụ thuộc vào giá trị của x:
a) A=\(3\left(x-1\right)^2-\left(x+1\right)^2+2\left(x-3\right)\left(x+3\right)-\left(2x+3\right)^2-\left(5-20x\right)\)
b) B=\(-x\left(x +2\right)^2+\left(2x+1\right)^2+\left(x+3\right)\left(x^2-3x+9\right)-1\)
rút gọn biểu thức
a/ 2x\(\left(2x-1\right)^2-3x\left(x+3\right)\left(x-3\right)-4x\left(x+1\right)^2\)
b/ \(\left(a-b+c\right)^2-\left(b-c\right)^2+2ab-2ac\)
c/ \(\left(3x+1\right)^2-2\left(3x+1\right)\left(3x+5\right)+\left(3x+5\right)^2\)
d/ ( 3 + 1 ) \(\left(3^2+1\right)\left(3^4+1\right)\left(3^8+1\right)\left(3^{16}+1\right)\left(3^{32}+1\right)\)
BT1: Viết các biểu thức sau dưới dạng bình phương1 tổng(hiệu):
a, \(x^2+12x+36\)
b, \(x^2-x+\dfrac{1}{4}\)
BT2: Rút gọn biểu thức:
a, \(\left(x^2-1\right)^3-\left(x^4+x^2+1\right)\left(x^2-1\right)\)
b, \(\left(x^4-3x^2+9\right)\left(x^2+3\right)-\left(3+x^2\right)^3\)
c, \(\left(x-3\right)^3-\left(x-3\right)\left(x^2+3x+9\right)+6\left(x+1\right)^2\)
BT3: Tìm x:
a, \(\left(x+2\right)\left(x^2-2x+4\right)-x\left(x^2+2\right)=15\)
b, \(\left(x+3\right)^3-x\left(3x+1\right)^2+\left(2x+1\right)\left(4x^2-2x+1\right)=28\)
c, \(\left(x^2-1\right)^3-\left(x^4+x^2+1\right)\left(x^2+1\right)=0\)
BT4: Tìm GTNN của:
\(A=x^2-4x+7\)
\(B=2x^2-6x\)
Giúp mình với mình cần gấp!!! Cảm ơn các bạn nhiều nha!!!
1>Tínk:
1, \(\left(x+y\right)^3-\left(x-y\right)^3\)
2, 64-24y+\(3y^2-\dfrac{1}{8}y^3\)
3, \(216x^3+18x^2y+\dfrac{1}{2}xy^2+\dfrac{1}{216}y^3\)
4, \(\left(2x+y\right)^3-3.\left(x+y\right).\left(x-y\right)\)
5, \(\left(x-y\right)^3+3.\left(x+y\right).\left(x^2+y^2\right)\)