Getal & Ruimte (13e editie) - 3 vwo
'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 \(K\kern{-.8pt}L=53\text{,}\) \(\angle K=37\degree\) en \(\angle L=90\degree\text{.}\) Tangens (1) 007m - Sinus, cosinus en tangens - basis - 0ms a Tangens in \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) geeft \(\tan(\angle K)={L\kern{-.8pt}M \over K\kern{-.8pt}L}\) ofwel \(\tan(37\degree)={L\kern{-.8pt}M \over 53}\text{.}\) 1p ○ Hieruit volgt \(L\kern{-.8pt}M=53⋅\tan(37\degree)\text{.}\) 1p ○ Dus \(L\kern{-.8pt}M≈39{,}9\text{.}\) 1p 3p b Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(Q\kern{-.8pt}R=58\text{,}\) \(\angle P=47\degree\) 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 \(\tan(47\degree)={58 \over P\kern{-.8pt}Q}\text{.}\) 1p ○ Hieruit volgt \(P\kern{-.8pt}Q={58 \over \tan(47\degree)}\text{.}\) 1p ○ Dus \(P\kern{-.8pt}Q≈54{,}1\text{.}\) 1p 3p c Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(P\kern{-.8pt}Q=53\text{,}\) \(Q\kern{-.8pt}R=50\) en \(\angle Q=90\degree\text{.}\) Tangens (3) 007o - Sinus, cosinus en tangens - basis - 0ms c Tangens in \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) geeft \(\tan(\angle P)={Q\kern{-.8pt}R \over P\kern{-.8pt}Q}\) ofwel \(\tan(\angle P)={50 \over 53}\text{.}\) 1p ○ Hieruit volgt \(\angle P=\tan^{-1}({50 \over 53})\text{.}\) 1p ○ Dus \(\angle P≈43{,}3\degree\text{.}\) 1p |
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| 3 vwo | 6.4 De sinus en de cosinus |
opgave 13p a Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(A\kern{-.8pt}C=78\text{,}\) \(\angle A=40\degree\) en \(\angle B=90\degree\text{.}\) Sinus (1) 007g - Sinus, cosinus en tangens - basis - 0ms a Sinus in \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) geeft \(\sin(\angle A)={B\kern{-.8pt}C \over A\kern{-.8pt}C}\) ofwel \(\sin(40\degree)={B\kern{-.8pt}C \over 78}\text{.}\) 1p ○ Hieruit volgt \(B\kern{-.8pt}C=78⋅\sin(40\degree)\text{.}\) 1p ○ Dus \(B\kern{-.8pt}C≈50{,}1\text{.}\) 1p 3p b Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(Q\kern{-.8pt}R=34\text{,}\) \(\angle P=57\degree\) en \(\angle Q=90\degree\text{.}\) Sinus (2) 007h - Sinus, cosinus en tangens - basis - 0ms b Sinus in \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) geeft \(\sin(\angle P)={Q\kern{-.8pt}R \over P\kern{-.8pt}R}\) ofwel \(\sin(57\degree)={34 \over P\kern{-.8pt}R}\text{.}\) 1p ○ Hieruit volgt \(P\kern{-.8pt}R={34 \over \sin(57\degree)}\text{.}\) 1p ○ Dus \(P\kern{-.8pt}R≈40{,}5\text{.}\) 1p 3p c Gegeven is \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) met \(K\kern{-.8pt}L=43\text{,}\) \(L\kern{-.8pt}M=66\) en \(\angle K=90\degree\text{.}\) Sinus (3) 007i - Sinus, cosinus en tangens - basis - 0ms c Sinus in \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) geeft \(\sin(\angle M)={K\kern{-.8pt}L \over L\kern{-.8pt}M}\) ofwel \(\sin(\angle M)={43 \over 66}\text{.}\) 1p ○ Hieruit volgt \(\angle M=\sin^{-1}({43 \over 66})\text{.}\) 1p ○ Dus \(\angle M≈40{,}7\degree\text{.}\) 1p 3p d Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(P\kern{-.8pt}Q=46\text{,}\) \(\angle Q=47\degree\) en \(\angle R=90\degree\text{.}\) Cosinus (1) 007j - Sinus, cosinus en tangens - basis - 0ms d Cosinus in \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) geeft \(\cos(\angle Q)={Q\kern{-.8pt}R \over P\kern{-.8pt}Q}\) ofwel \(\cos(47\degree)={Q\kern{-.8pt}R \over 46}\text{.}\) 1p ○ Hieruit volgt \(Q\kern{-.8pt}R=46⋅\cos(47\degree)\text{.}\) 1p ○ Dus \(Q\kern{-.8pt}R≈31{,}4\text{.}\) 1p opgave 23p a Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(P\kern{-.8pt}R=46\text{,}\) \(\angle R=42\degree\) en \(\angle P=90\degree\text{.}\) Cosinus (2) 007k - Sinus, cosinus en tangens - basis - 0ms a Cosinus in \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) geeft \(\cos(\angle R)={P\kern{-.8pt}R \over Q\kern{-.8pt}R}\) ofwel \(\cos(42\degree)={46 \over Q\kern{-.8pt}R}\text{.}\) 1p ○ Hieruit volgt \(Q\kern{-.8pt}R={46 \over \cos(42\degree)}\text{.}\) 1p ○ Dus \(Q\kern{-.8pt}R≈61{,}9\text{.}\) 1p 3p b Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(Q\kern{-.8pt}R=47\text{,}\) \(P\kern{-.8pt}Q=62\) en \(\angle R=90\degree\text{.}\) Cosinus (3) 007l - Sinus, cosinus en tangens - basis - 1ms 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 \(\cos(\angle Q)={47 \over 62}\text{.}\) 1p ○ Hieruit volgt \(\angle Q=\cos^{-1}({47 \over 62})\text{.}\) 1p ○ Dus \(\angle Q≈40{,}7\degree\text{.}\) 1p |