Getal & Ruimte (12e editie) - vwo wiskunde B
'Sinus, cosinus en tangens'.
| 3 vwo | 6.3 Berekeningen met de tangens |
opgave 13p a Gegeven is \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) met \(K\kern{-.8pt}M=21\text{,}\) \(\angle M=43\degree\) en \(\angle K=90\degree\text{.}\) Tangens (1) 007m - Sinus, cosinus en tangens - basis a Tangens in \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) geeft \(\tan(\angle M)={K\kern{-.8pt}L \over K\kern{-.8pt}M}\) ofwel \(\tan(43\degree)={K\kern{-.8pt}L \over 21}\text{.}\) 1p ○ Hieruit volgt \(K\kern{-.8pt}L=21⋅\tan(43\degree)\text{.}\) 1p ○ Dus \(K\kern{-.8pt}L≈19{,}6\text{.}\) 1p 3p b Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(B\kern{-.8pt}C=49\text{,}\) \(\angle A=50\degree\) en \(\angle B=90\degree\text{.}\) Tangens (2) 007n - Sinus, cosinus en tangens - basis b Tangens in \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) geeft \(\tan(\angle A)={B\kern{-.8pt}C \over A\kern{-.8pt}B}\) ofwel \(\tan(50\degree)={49 \over A\kern{-.8pt}B}\text{.}\) 1p ○ Hieruit volgt \(A\kern{-.8pt}B={49 \over \tan(50\degree)}\text{.}\) 1p ○ Dus \(A\kern{-.8pt}B≈41{,}1\text{.}\) 1p 3p c Gegeven is \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) met \(L\kern{-.8pt}M=42\text{,}\) \(K\kern{-.8pt}M=48\) en \(\angle M=90\degree\text{.}\) Tangens (3) 007o - Sinus, cosinus en tangens - basis c Tangens in \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) geeft \(\tan(\angle L)={K\kern{-.8pt}M \over L\kern{-.8pt}M}\) ofwel \(\tan(\angle L)={48 \over 42}\text{.}\) 1p ○ Hieruit volgt \(\angle L=\tan^{-1}({48 \over 42})\text{.}\) 1p ○ Dus \(\angle L≈48{,}8\degree\text{.}\) 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 \(P\kern{-.8pt}Q=80\text{,}\) \(\angle Q=43\degree\) en \(\angle R=90\degree\text{.}\) Sinus (1) 007g - Sinus, cosinus en tangens - basis 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 \(\sin(43\degree)={P\kern{-.8pt}R \over 80}\text{.}\) 1p ○ Hieruit volgt \(P\kern{-.8pt}R=80⋅\sin(43\degree)\text{.}\) 1p ○ Dus \(P\kern{-.8pt}R≈54{,}6\text{.}\) 1p 3p b Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(P\kern{-.8pt}Q=57\text{,}\) \(\angle R=31\degree\) en \(\angle P=90\degree\text{.}\) Sinus (2) 007h - Sinus, cosinus en tangens - basis b Sinus in \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) geeft \(\sin(\angle R)={P\kern{-.8pt}Q \over Q\kern{-.8pt}R}\) ofwel \(\sin(31\degree)={57 \over Q\kern{-.8pt}R}\text{.}\) 1p ○ Hieruit volgt \(Q\kern{-.8pt}R={57 \over \sin(31\degree)}\text{.}\) 1p ○ Dus \(Q\kern{-.8pt}R≈110{,}7\text{.}\) 1p 3p c Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(P\kern{-.8pt}R=53\text{,}\) \(P\kern{-.8pt}Q=77\) en \(\angle R=90\degree\text{.}\) Sinus (3) 007i - Sinus, cosinus en tangens - basis c Sinus in \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) geeft \(\sin(\angle Q)={P\kern{-.8pt}R \over P\kern{-.8pt}Q}\) ofwel \(\sin(\angle Q)={53 \over 77}\text{.}\) 1p ○ Hieruit volgt \(\angle Q=\sin^{-1}({53 \over 77})\text{.}\) 1p ○ Dus \(\angle Q≈43{,}5\degree\text{.}\) 1p 3p d Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(P\kern{-.8pt}Q=44\text{,}\) \(\angle Q=50\degree\) en \(\angle R=90\degree\text{.}\) Cosinus (1) 007j - Sinus, cosinus en tangens - basis d Cosinus in \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) geeft \(\cos(\angle Q)={Q\kern{-.8pt}R \over P\kern{-.8pt}Q}\) ofwel \(\cos(50\degree)={Q\kern{-.8pt}R \over 44}\text{.}\) 1p ○ Hieruit volgt \(Q\kern{-.8pt}R=44⋅\cos(50\degree)\text{.}\) 1p ○ Dus \(Q\kern{-.8pt}R≈28{,}3\text{.}\) 1p opgave 23p a Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(Q\kern{-.8pt}R=27\text{,}\) \(\angle Q=46\degree\) en \(\angle R=90\degree\text{.}\) Cosinus (2) 007k - Sinus, cosinus en tangens - basis a Cosinus in \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) geeft \(\cos(\angle Q)={Q\kern{-.8pt}R \over P\kern{-.8pt}Q}\) ofwel \(\cos(46\degree)={27 \over P\kern{-.8pt}Q}\text{.}\) 1p ○ Hieruit volgt \(P\kern{-.8pt}Q={27 \over \cos(46\degree)}\text{.}\) 1p ○ Dus \(P\kern{-.8pt}Q≈38{,}9\text{.}\) 1p 3p b Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(Q\kern{-.8pt}R=46\text{,}\) \(P\kern{-.8pt}Q=51\) en \(\angle R=90\degree\text{.}\) Cosinus (3) 007l - Sinus, cosinus en tangens - basis b Cosinus in \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) geeft \(\cos(\angle Q)={Q\kern{-.8pt}R \over P\kern{-.8pt}Q}\) ofwel \(\cos(\angle Q)={46 \over 51}\text{.}\) 1p ○ Hieruit volgt \(\angle Q=\cos^{-1}({46 \over 51})\text{.}\) 1p ○ Dus \(\angle Q≈25{,}6\degree\text{.}\) 1p |