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 \(L\kern{-.8pt}M=38\text{,}\) \(\angle L=35\degree\) en \(\angle M=90\degree\text{.}\) Tangens (1) 007m - Sinus, cosinus en tangens - basis - 0ms a Tangens in \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) geeft \(\tan(\angle L)={K\kern{-.8pt}M \over L\kern{-.8pt}M}\) ofwel \(\tan(35\degree)={K\kern{-.8pt}M \over 38}\text{.}\) 1p ○ Hieruit volgt \(K\kern{-.8pt}M=38⋅\tan(35\degree)\text{.}\) 1p ○ Dus \(K\kern{-.8pt}M≈26{,}6\text{.}\) 1p 3p b Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(Q\kern{-.8pt}R=52\text{,}\) \(\angle P=50\degree\) 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 \(\tan(50\degree)={52 \over P\kern{-.8pt}Q}\text{.}\) 1p ○ Hieruit volgt \(P\kern{-.8pt}Q={52 \over \tan(50\degree)}\text{.}\) 1p ○ Dus \(P\kern{-.8pt}Q≈43{,}6\text{.}\) 1p 3p c Gegeven is \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) met \(K\kern{-.8pt}M=36\text{,}\) \(K\kern{-.8pt}L=45\) en \(\angle K=90\degree\text{.}\) Tangens (3) 007o - Sinus, cosinus en tangens - basis - 0ms c Tangens in \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) geeft \(\tan(\angle M)={K\kern{-.8pt}L \over K\kern{-.8pt}M}\) ofwel \(\tan(\angle M)={45 \over 36}\text{.}\) 1p ○ Hieruit volgt \(\angle M=\tan^{-1}({45 \over 36})\text{.}\) 1p ○ Dus \(\angle M≈51{,}3\degree\text{.}\) 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 \(P\kern{-.8pt}Q=73\text{,}\) \(\angle Q=53\degree\) 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 \(\sin(53\degree)={P\kern{-.8pt}R \over 73}\text{.}\) 1p ○ Hieruit volgt \(P\kern{-.8pt}R=73⋅\sin(53\degree)\text{.}\) 1p ○ Dus \(P\kern{-.8pt}R≈58{,}3\text{.}\) 1p 3p b Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(A\kern{-.8pt}C=28\text{,}\) \(\angle B=56\degree\) en \(\angle C=90\degree\text{.}\) Sinus (2) 007h - Sinus, cosinus en tangens - basis - 0ms b Sinus in \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) geeft \(\sin(\angle B)={A\kern{-.8pt}C \over A\kern{-.8pt}B}\) ofwel \(\sin(56\degree)={28 \over A\kern{-.8pt}B}\text{.}\) 1p ○ Hieruit volgt \(A\kern{-.8pt}B={28 \over \sin(56\degree)}\text{.}\) 1p ○ Dus \(A\kern{-.8pt}B≈33{,}8\text{.}\) 1p 3p c Gegeven is \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) met \(K\kern{-.8pt}M=42\text{,}\) \(K\kern{-.8pt}L=61\) en \(\angle M=90\degree\text{.}\) Sinus (3) 007i - Sinus, cosinus en tangens - basis - 0ms c Sinus in \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) geeft \(\sin(\angle L)={K\kern{-.8pt}M \over K\kern{-.8pt}L}\) ofwel \(\sin(\angle L)={42 \over 61}\text{.}\) 1p ○ Hieruit volgt \(\angle L=\sin^{-1}({42 \over 61})\text{.}\) 1p ○ Dus \(\angle L≈43{,}5\degree\text{.}\) 1p 3p d Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(P\kern{-.8pt}Q=58\text{,}\) \(\angle Q=55\degree\) 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 \(\cos(55\degree)={Q\kern{-.8pt}R \over 58}\text{.}\) 1p ○ Hieruit volgt \(Q\kern{-.8pt}R=58⋅\cos(55\degree)\text{.}\) 1p ○ Dus \(Q\kern{-.8pt}R≈33{,}3\text{.}\) 1p opgave 23p a Gegeven is \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) met \(L\kern{-.8pt}M=47\text{,}\) \(\angle L=41\degree\) en \(\angle M=90\degree\text{.}\) Cosinus (2) 007k - Sinus, cosinus en tangens - basis - 0ms a Cosinus in \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) geeft \(\cos(\angle L)={L\kern{-.8pt}M \over K\kern{-.8pt}L}\) ofwel \(\cos(41\degree)={47 \over K\kern{-.8pt}L}\text{.}\) 1p ○ Hieruit volgt \(K\kern{-.8pt}L={47 \over \cos(41\degree)}\text{.}\) 1p ○ Dus \(K\kern{-.8pt}L≈62{,}3\text{.}\) 1p 3p b Gegeven is \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) met \(K\kern{-.8pt}M=38\text{,}\) \(L\kern{-.8pt}M=44\) en \(\angle K=90\degree\text{.}\) Cosinus (3) 007l - Sinus, cosinus en tangens - basis - 1ms b Cosinus in \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) geeft \(\cos(\angle M)={K\kern{-.8pt}M \over L\kern{-.8pt}M}\) ofwel \(\cos(\angle M)={38 \over 44}\text{.}\) 1p ○ Hieruit volgt \(\angle M=\cos^{-1}({38 \over 44})\text{.}\) 1p ○ Dus \(\angle M≈30{,}3\degree\text{.}\) 1p |