Question

Tìm x,y :

\(\left(x+1,5\right)^8+\left(2,7-y\right)^{10}=0\)

Giúp mk với !

Answer 1

\(\left(x+1.5\right)^8+\left(2.7-y\right)^{10}=0\)

\(\Leftrightarrow\left\{{}\begin{matrix}x+1.5=0\\2.7-y=0\end{matrix}\right.\)

\(\Leftrightarrow\left\{{}\begin{matrix}x=-1.5\\y=2.7\end{matrix}\right.\)

Vậy : phương trình có cặp nghiệm \(\left(x,y\right)=\left(-1.5,2.7\right)\)

Answer 2

(x+1,5)⁸+(2,7-y)¹⁰=0

⇒\(\left[{}\begin{matrix}\left(x+1,5\right)^8\\\left(2,7-y\right)^{10}\end{matrix}\right.=0\)

⇒\(\left[{}\begin{matrix}x+1,5=0\\2,7-y=0\end{matrix}\right.\) ⇒\(\left[{}\begin{matrix}x=0-1,5\\y=2,7-0\end{matrix}\right.\) ⇒\(\left[{}\begin{matrix}x=-1,5\\y=2,7\end{matrix}\right.\)

 

Answer 3

Ta có: \(\left(x+1.5\right)^8\ge0\forall x\)

\(\left(2,7-y\right)^{10}\ge0\forall y\)

Do đó: \(\left(x+1.5\right)^8+\left(2.7-y\right)^{10}\ge0\forall x,y\)

Dấu '=' xảy ra khi \(\left(x,y\right)=\left(-1,5;2,7\right)\)