Question

Trong không gian Oxyz, cho 2 véc tơ a = (-1;2x - 1;1 - 3z) và vec to b = (2+3y; -1;-2). Khi a = b thì tổng T = x+ 2y²+32z³bằng

Answer 1

\(\overrightarrow{a}=\left(-1;2x-1;1-3z\right)\)

\(\overrightarrow{b}=\left(2+3y;-1;-2\right)\)

\(\overrightarrow{a}=\overrightarrow{b}\Leftrightarrow\left\{{}\begin{matrix}2+3y=-1\\2x-1=-1\\1-3z=-2\end{matrix}\right.\)

\(\Leftrightarrow\left\{{}\begin{matrix}x=0\\y=-1\\z=1\end{matrix}\right.\)

\(\Rightarrow T=x+2y^2+32z^3=0+2.\left(-1\right)^2+32.1^3=35\)