x4+y4=1=>x4=1−y4≤1<=>−1≤x≤1x4+y4=1=>x4=1−y4≤1<=>−1≤x≤1
y4=1−x4≤1=>−1≤y≤1y4=1−x4≤1=>−1≤y≤1
=>x;y∈[−1;1]=>x;y∈[−1;1]
mà x3+y3=1=>x3=1−y3≥0=>x≥0=>x∈[0;1]x3+y3=1=>x3=1−y3≥0=>x≥0=>x∈[0;1]
y3=1−x3≥0=>y≥0=>y∈[0;1]y3=1−x3≥0=>y≥0=>y∈[0;1]
§3. Phương trình và hệ phương trình bậc nhất nhiều ẩn
Các câu hỏi tương tự
Giải hệ phương trình:
a) \(\left\{{}\begin{matrix}y\left(x+y+1\right)=3\\\left(x+y\right)^2-\dfrac{4}{y^2}=0\end{matrix}\right.\)
b) \(\left\{{}\begin{matrix}x-\dfrac{1}{x}=y-\dfrac{1}{y}\\2y=x^3+1\end{matrix}\right.\)
Em đang cần gấp ạ !!! Cảm ơn mọi người nhiều ạ !!!
Giải các hệ
left{{}begin{matrix}sqrt{x+y}+sqrt{2x+y+2}73x+2y23end{matrix}right.
left{{}begin{matrix}x^2+y+x^3y+xy^2+xyfrac{-5}{4}x^4+y^2+xyleft(1+2xright)frac{-5}{4}end{matrix}right.
left{{}begin{matrix}left(x^2+1right)+yleft(x+yright)7yleft(x^2+1right)left(x+y-2right)-yend{matrix}right.
left{{}begin{matrix}xleft(x+y+1right)3left(x+yright)^2-frac{5}{x^2}-1end{matrix}right.
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Giải các hệ
\(\left\{{}\begin{matrix}\sqrt{x+y}+\sqrt{2x+y+2}=7\\3x+2y=23\end{matrix}\right.\)
\(\left\{{}\begin{matrix}x^2+y+x^3y+xy^2+xy=\frac{-5}{4}\\x^4+y^2+xy\left(1+2x\right)=\frac{-5}{4}\end{matrix}\right.\)
\(\left\{{}\begin{matrix}\left(x^2+1\right)+y\left(x+y\right)=7y\\\left(x^2+1\right)\left(x+y-2\right)=-y\end{matrix}\right.\)
\(\left\{{}\begin{matrix}x\left(x+y+1\right)=3\\\left(x+y\right)^2-\frac{5}{x^2}=-1\end{matrix}\right.\)
hệ phương trình
1, left{{}begin{matrix}3x6x-3y2end{matrix}right.
2,left{{}begin{matrix}3x+5y152y-7end{matrix}right.
3, left{{}begin{matrix}7x-2y13x+y6end{matrix}right.
4, left{{}begin{matrix}3left(x+yright)+92left(x-yright)2left(x+yright)3left(x-yright)+11end{matrix}right.
5 , left{{}begin{matrix}3left(x+yright)+5left(x-yright)12-5left(x+yright)+2left(x-yright)11end{matrix}right.
6 , left{{}begin{matrix}2left(3x-2right)-45left(3y+2right)4left(3x-2right)+7left(3y+2right)-2end{matrix}right...
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hệ phương trình
1, \(\left\{{}\begin{matrix}3x=6\\x-3y=2\end{matrix}\right.\)
2,\(\left\{{}\begin{matrix}3x+5y=15\\2y=-7\end{matrix}\right.\)
3, \(\left\{{}\begin{matrix}7x-2y=1\\3x+y=6\end{matrix}\right.\)
4, \(\left\{{}\begin{matrix}3\left(x+y\right)+9=2\left(x-y\right)\\2\left(x+y\right)=3\left(x-y\right)+11\end{matrix}\right.\)
5 , \(\left\{{}\begin{matrix}3\left(x+y\right)+5\left(x-y\right)=12\\-5\left(x+y\right)+2\left(x-y\right)=11\end{matrix}\right.\)
6 , \(\left\{{}\begin{matrix}2\left(3x-2\right)-4=5\left(3y+2\right)\\4\left(3x-2\right)+7\left(3y+2\right)=-2\end{matrix}\right.\)
7, \(\left\{{}\begin{matrix}\frac{1}{x}+\frac{1}{y}=\frac{4}{5}\\\frac{1}{x}-\frac{1}{y}=\frac{1}{5}\end{matrix}\right.\)
8 , \(\left\{{}\begin{matrix}\frac{15}{x}-\frac{7}{y}=9\\\frac{4}{x}+\frac{9}{y}=35\end{matrix}\right.\)
Giải pt sau bằng cách đặt ẩn phụ
1, \(\left\{{}\begin{matrix}x^2+y+x^3y+xy^2+xy=-\frac{5}{4}\\x^4+y^2+xy\left(1+2x\right)=-\frac{5}{4}\end{matrix}\right.\)
2, \(\left\{{}\begin{matrix}x^3+3x^2-13x-15=\frac{8}{y^3}-\frac{8}{y}\\y^2+4=5y^2\left(x^2+2x+2\right)\end{matrix}\right.\)
Giải các hệ phương trình
left{{}begin{matrix}frac{1}{x+1}+frac{1}{y}frac{1}{3}frac{1}{left(x+1right)^2}-frac{1}{y^2}frac{1}{4}end{matrix}right.
left{{}begin{matrix}left(x+mright)^2-y^2+yleft(x+mright)11x+2y7-mend{matrix}right.
left{{}begin{matrix}left(x+aright)^2+2left(y-aright)^2-left(x+aright)left(y-aright)2x+y2end{matrix}right.
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Giải các hệ phương trình
\(\left\{{}\begin{matrix}\frac{1}{x+1}+\frac{1}{y}=\frac{1}{3}\\\frac{1}{\left(x+1\right)^2}-\frac{1}{y^2}=\frac{1}{4}\end{matrix}\right.\)
\(\left\{{}\begin{matrix}\left(x+m\right)^2-y^2+y\left(x+m\right)=11\\x+2y=7-m\end{matrix}\right.\)
\(\left\{{}\begin{matrix}\left(x+a\right)^2+2\left(y-a\right)^2-\left(x+a\right)\left(y-a\right)=2\\x+y=2\end{matrix}\right.\)
Giải các hệ phương trình :
a. left{{}begin{matrix}2x-3y1x+2y3end{matrix}right.
b. left{{}begin{matrix}2x+4y54x-2y2end{matrix}right.
c. left{{}begin{matrix}dfrac{2}{3}x+dfrac{1}{2}ydfrac{2}{3}dfrac{1}{3}x-dfrac{3}{4}ydfrac{1}{2}end{matrix}right.
d. left{{}begin{matrix}0,3x-0,2y0,50,5x+0,4y1,2end{matrix}right.
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Giải các hệ phương trình :
a. \(\left\{{}\begin{matrix}2x-3y=1\\x+2y=3\end{matrix}\right.\)
b. \(\left\{{}\begin{matrix}2x+4y=5\\4x-2y=2\end{matrix}\right.\)
c. \(\left\{{}\begin{matrix}\dfrac{2}{3}x+\dfrac{1}{2}y=\dfrac{2}{3}\\\dfrac{1}{3}x-\dfrac{3}{4}y=\dfrac{1}{2}\end{matrix}\right.\)
d. \(\left\{{}\begin{matrix}0,3x-0,2y=0,5\\0,5x+0,4y=1,2\end{matrix}\right.\)
Giải hệ pt
\(\left\{{}\begin{matrix}\\\\\end{matrix}\right.\)x2-2xy+y2+x-y=0 x2+2y2=0
\(\left\{{}\begin{matrix}\\\\\end{matrix}\right.\)x2-xy+y-7=0 x2+xy-2y=4(x-1)
Giai hệ PT sau:\(\left\{{}\begin{matrix}2x^2+xy=3y+6\\2y^2+xy=3x+6\end{matrix}\right.\)
\(\left\{{}\begin{matrix}xy+x^2=1+y\\yx+y^2=1+x\end{matrix}\right.\)
giải hệ Pt : \(\left\{{}\begin{matrix}x^2\left(y+1\right)\left(x+y+1\right)=3x^2-4x+1\\xy+x+1=x^2\end{matrix}\right.\)