Getal & Ruimte (13e editie) - vwo wiskunde B
'Sinus, cosinus en tangens'.
| 3 vwo | 6.3 Berekeningen met de tangens |
opgave 13p a Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(B\kern{-.8pt}C=33\text{,}\) \(\angle B=49\degree\) en \(\angle C=90\degree\text{.}\) Tangens (1) 007m - Sinus, cosinus en tangens - basis - 0ms a Tangens in \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) geeft \(\tan(\angle B)={A\kern{-.8pt}C \over B\kern{-.8pt}C}\) ofwel \(\tan(49\degree)={A\kern{-.8pt}C \over 33}\text{.}\) 1p ○ Hieruit volgt \(A\kern{-.8pt}C=33⋅\tan(49\degree)\text{.}\) 1p ○ Dus \(A\kern{-.8pt}C≈38{,}0\text{.}\) 1p 3p b Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(Q\kern{-.8pt}R=25\text{,}\) \(\angle P=48\degree\) en \(\angle Q=90\degree\text{.}\) Tangens (2) 007n - Sinus, cosinus en tangens - basis - 0ms b Tangens in \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) geeft \(\tan(\angle P)={Q\kern{-.8pt}R \over P\kern{-.8pt}Q}\) ofwel \(\tan(48\degree)={25 \over P\kern{-.8pt}Q}\text{.}\) 1p ○ Hieruit volgt \(P\kern{-.8pt}Q={25 \over \tan(48\degree)}\text{.}\) 1p ○ Dus \(P\kern{-.8pt}Q≈22{,}5\text{.}\) 1p 3p c Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(B\kern{-.8pt}C=35\text{,}\) \(A\kern{-.8pt}C=39\) en \(\angle C=90\degree\text{.}\) Tangens (3) 007o - Sinus, cosinus en tangens - basis - 0ms c Tangens in \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) geeft \(\tan(\angle B)={A\kern{-.8pt}C \over B\kern{-.8pt}C}\) ofwel \(\tan(\angle B)={39 \over 35}\text{.}\) 1p ○ Hieruit volgt \(\angle B=\tan^{-1}({39 \over 35})\text{.}\) 1p ○ Dus \(\angle B≈48{,}1\degree\text{.}\) 1p |
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| 3 vwo | 6.4 De sinus en de cosinus |
opgave 13p a Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(P\kern{-.8pt}Q=63\text{,}\) \(\angle Q=40\degree\) en \(\angle R=90\degree\text{.}\) Sinus (1) 007g - Sinus, cosinus en tangens - basis - 0ms a Sinus in \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) geeft \(\sin(\angle Q)={P\kern{-.8pt}R \over P\kern{-.8pt}Q}\) ofwel \(\sin(40\degree)={P\kern{-.8pt}R \over 63}\text{.}\) 1p ○ Hieruit volgt \(P\kern{-.8pt}R=63⋅\sin(40\degree)\text{.}\) 1p ○ Dus \(P\kern{-.8pt}R≈40{,}5\text{.}\) 1p 3p b Gegeven is \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) met \(K\kern{-.8pt}L=37\text{,}\) \(\angle M=39\degree\) en \(\angle K=90\degree\text{.}\) Sinus (2) 007h - Sinus, cosinus en tangens - basis - 0ms b Sinus in \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) geeft \(\sin(\angle M)={K\kern{-.8pt}L \over L\kern{-.8pt}M}\) ofwel \(\sin(39\degree)={37 \over L\kern{-.8pt}M}\text{.}\) 1p ○ Hieruit volgt \(L\kern{-.8pt}M={37 \over \sin(39\degree)}\text{.}\) 1p ○ Dus \(L\kern{-.8pt}M≈58{,}8\text{.}\) 1p 3p c Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(A\kern{-.8pt}C=21\text{,}\) \(A\kern{-.8pt}B=30\) en \(\angle C=90\degree\text{.}\) Sinus (3) 007i - Sinus, cosinus en tangens - basis - 0ms c Sinus in \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) geeft \(\sin(\angle B)={A\kern{-.8pt}C \over A\kern{-.8pt}B}\) ofwel \(\sin(\angle B)={21 \over 30}\text{.}\) 1p ○ Hieruit volgt \(\angle B=\sin^{-1}({21 \over 30})\text{.}\) 1p ○ Dus \(\angle B≈44{,}4\degree\text{.}\) 1p 3p d Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(P\kern{-.8pt}R=52\text{,}\) \(\angle P=37\degree\) en \(\angle Q=90\degree\text{.}\) Cosinus (1) 007j - Sinus, cosinus en tangens - basis - 0ms d Cosinus in \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) geeft \(\cos(\angle P)={P\kern{-.8pt}Q \over P\kern{-.8pt}R}\) ofwel \(\cos(37\degree)={P\kern{-.8pt}Q \over 52}\text{.}\) 1p ○ Hieruit volgt \(P\kern{-.8pt}Q=52⋅\cos(37\degree)\text{.}\) 1p ○ Dus \(P\kern{-.8pt}Q≈41{,}5\text{.}\) 1p opgave 23p a Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(P\kern{-.8pt}Q=24\text{,}\) \(\angle P=51\degree\) en \(\angle Q=90\degree\text{.}\) Cosinus (2) 007k - Sinus, cosinus en tangens - basis - 0ms a Cosinus in \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) geeft \(\cos(\angle P)={P\kern{-.8pt}Q \over P\kern{-.8pt}R}\) ofwel \(\cos(51\degree)={24 \over P\kern{-.8pt}R}\text{.}\) 1p ○ Hieruit volgt \(P\kern{-.8pt}R={24 \over \cos(51\degree)}\text{.}\) 1p ○ Dus \(P\kern{-.8pt}R≈38{,}1\text{.}\) 1p 3p b Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(P\kern{-.8pt}Q=35\text{,}\) \(P\kern{-.8pt}R=58\) en \(\angle Q=90\degree\text{.}\) Cosinus (3) 007l - Sinus, cosinus en tangens - basis - 0ms b Cosinus in \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) geeft \(\cos(\angle P)={P\kern{-.8pt}Q \over P\kern{-.8pt}R}\) ofwel \(\cos(\angle P)={35 \over 58}\text{.}\) 1p ○ Hieruit volgt \(\angle P=\cos^{-1}({35 \over 58})\text{.}\) 1p ○ Dus \(\angle P≈52{,}9\degree\text{.}\) 1p |