Các câu hỏi tương tự
1. cho x+y=7 va xy=8 gia tri cua bieu thuc x3+y3 = ?
2. gia tri lon nhat cua bieu thuc B= 1+3x-x2 la ?
1. cho x+y=7 va xy=8 gia tri cua bieu thuc x3+y3 = ?
2. gia tri lon nhat cua bieu thuc B= 1+3x-x2 la ?
khi x+y=3 va xy=-1 thi gia tri bieu thuc x^3+y^3/3^2+1=?
cho x,y khac nhau biet x2-y=y2-x. tinh gia tri cua bieu thuc A=x2+2xy+y2-3x-3y
cho x,y,z đôi một khac nhau va 1/x +1/y+1/z=0 .tinh gia tri bieu thuc A=(x.y/x2+2yz)+(xz/y2+2xz)+(xy/z2+2xy)
1.
a.(-xy)(-2x2y+3xy-7x)
b.(1/6x2y2)(-0,3x2y-0,4xy+1)
c.(x+y)(x2+2xy+y2)
d.(x-y)(x2-2xy+y2)
2.
a.(x-y)(x2+xy+y2)
b.(x+y)(x2-xy+y2)
c.(4x-1)(6y+1)-3x(8y+4/3)
cho x+y =1 . tinh gia tri cua bieu thuc A=x^3+y^3+3xy
chox-y=1. tinh gia tri cua bieu thuc B=x^3-y^3-3xy
cho x+y=1 . tinh gia tri cua bieu thuc C=x^3+y^3+3xy(x^2+y^2)+6x^2*y^2(x+y)
Tinh gia tri cua bieu thuc A=x-2009/2009x+y
Biet x^2-2y^2=xy( voi 2009x+y khac 0 )
1. biết x2-2y2=xy,y\(\ne\)0,x+y\(\ne\)0. thì gia tri cua bieu thuc Q=\(\frac{x+y}{x-y}\)=
2.cho x\(\ne\)0,y\(\ne\)0 thoa man x+y=4 ;xy=2 .gia tri cua bieu thuc A=\(\frac{1}{x^3}+\frac{1}{y^3}\)la
3.gia tri cua bieu thuc A=\(\frac{81^8-1}{\left(3^4+1\right)\left(3^8+1\right)\left(3^{16}+1\right)}\)la