\(A=x^2y-x^3-3xyz-4+3xyz+1=x^2y-x^3-3\)
\(=\dfrac{1}{4}\cdot4-\left(-\dfrac{1}{8}\right)-3\)
=1-3+1/8
=-2+1/8=-15/8
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tinh gia tri bieu thuc A tai x=\(\dfrac{-1}{2}\);y=4;z=6
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tinh gia tri bieu thuc:
a,3x^4+5x^2y^2+2y^4+2y^2 biet rang x^2+y^2=1
tinh gia tri bieu thuc:
a,3x^4+5x^2y^2+2y^4+2y^2 biet rang x^2+y^2=1
tinh gia tri bieu thuc:
a,3x^4+5x^2y^2+2y^4+2y^2 biet rang x^2+y^2=1
tinh gia tri cac bieu thuc sau:3x^4+5x^2y^2+2y^4+2y^2biet rang x^2+y^2=1
tinh gia tri cua bieu thuc:
3x^4+5x^2y^2+2y^4+2y^2 biet rang x^2+y^2=1