Getal & Ruimte (13e editie) - vwo wiskunde B
'Stelsels oplossen'.
| vwo wiskunde B | 4.1 Stelsels vergelijkingen |
opgave 1Los exact op. 3p a \(\begin{cases}a+6b=-5 \\ 4a-6b=-5\end{cases}\) Eliminatie (1) 003f - Stelsels oplossen - basis - 361ms - dynamic variables a Optellen geeft \(5a=-10\text{,}\) dus \(a=-2\text{.}\) 1p ○ \(\begin{rcases}a+6b=-5 \\ a=-2\end{rcases}\begin{matrix}-2+6b=-5 \\ 6b=-3 \\ b=-\frac{1}{2}\end{matrix}\) 1p ○ De oplossing is \((a, b)=(-2, -\frac{1}{2})\text{.}\) 1p 4p b \(\begin{cases}4a+2b=-1 \\ 3a+b=-4\end{cases}\) Eliminatie (2) 003g - Stelsels oplossen - basis - 15ms - dynamic variables b \(\begin{cases}4a+2b=-1 \\ 3a+b=-4\end{cases}\) \(\begin{vmatrix}1 \\ 2\end{vmatrix}\) geeft \(\begin{cases}4a+2b=-1 \\ 6a+2b=-8\end{cases}\) 1p ○ Aftrekken geeft \(-2a=7\text{,}\) dus \(a=-3\frac{1}{2}\text{.}\) 1p ○ \(\begin{rcases}4a+2b=-1 \\ a=-3\frac{1}{2}\end{rcases}\begin{matrix}4⋅-3\frac{1}{2}+2b=-1 \\ 2b=13 \\ b=6\frac{1}{2}\end{matrix}\) 1p ○ De oplossing is \((a, b)=(-3\frac{1}{2}, 6\frac{1}{2})\text{.}\) 1p 4p c \(\begin{cases}5x-4y=6 \\ 4x-3y=6\end{cases}\) Eliminatie (3) 003h - Stelsels oplossen - basis - 12ms - dynamic variables c \(\begin{cases}5x-4y=6 \\ 4x-3y=6\end{cases}\) \(\begin{vmatrix}3 \\ 4\end{vmatrix}\) geeft \(\begin{cases}15x-12y=18 \\ 16x-12y=24\end{cases}\) 1p ○ Aftrekken geeft \(-x=-6\text{,}\) dus \(x=6\text{.}\) 1p ○ \(\begin{rcases}5x-4y=6 \\ x=6\end{rcases}\begin{matrix}5⋅6-4y=6 \\ -4y=-24 \\ y=6\end{matrix}\) 1p ○ De oplossing is \((x, y)=(6, 6)\text{.}\) 1p 4p d \(\begin{cases}y=7x+3 \\ y=4x\end{cases}\) GelijkStellen 003i - Stelsels oplossen - basis - 2ms d Gelijk stellen geeft \(7x+3=4x\) 1p ○ \(3x=-3\) dus \(x=-1\) 1p ○ \(\begin{rcases}y=7x+3 \\ x=-1\end{rcases}\begin{matrix}y=7⋅-1+3 \\ y=-4\end{matrix}\) 1p ○ De oplossing is \((x, y)=(-1, -4)\text{.}\) 1p opgave 2Los exact op. 4p a \(\begin{cases}3p+2q=-3 \\ q=7p+24\end{cases}\) Substitutie (1) 003j - Stelsels oplossen - basis - 3ms - dynamic variables a Substitutie geeft \(3p+2(7p+24)=-3\) 1p ○ Haakjes wegwerken geeft 1p ○ \(\begin{rcases}q=7p+24 \\ p=-3\end{rcases}\begin{matrix}q=7⋅-3+24 \\ q=3\end{matrix}\) 1p ○ De oplossing is \((p, q)=(-3, 3)\text{.}\) 1p 4p b \(\begin{cases}x=5y+1 \\ y=7x+27\end{cases}\) Substitutie (2) 003k - Stelsels oplossen - basis - 1ms - dynamic variables b Substitutie geeft \(x=5(7x+27)+1\) 1p ○ Haakjes wegwerken geeft 1p ○ \(\begin{rcases}y=7x+27 \\ x=-4\end{rcases}\begin{matrix}y=7⋅-4+27 \\ y=-1\end{matrix}\) 1p ○ De oplossing is \((x, y)=(-4, -1)\text{.}\) 1p |