Getal & Ruimte (12e editie) - havo wiskunde B
'Sinus, cosinus en tangens'.
| 3 havo | 6.3 Berekeningen met de tangens |
opgave 13p a Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(P\kern{-.8pt}R=25\text{,}\) \(\angle R=38\degree\) en \(\angle P=90\degree\text{.}\) Tangens (1) 007m - Sinus, cosinus en tangens - basis - 0ms a Tangens in \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) geeft \(\tan(\angle R)={P\kern{-.8pt}Q \over P\kern{-.8pt}R}\) ofwel \(\tan(38\degree)={P\kern{-.8pt}Q \over 25}\text{.}\) 1p ○ Hieruit volgt \(P\kern{-.8pt}Q=25⋅\tan(38\degree)\text{.}\) 1p ○ Dus \(P\kern{-.8pt}Q≈19{,}5\text{.}\) 1p 3p b Gegeven is \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) met \(L\kern{-.8pt}M=48\text{,}\) \(\angle K=59\degree\) en \(\angle L=90\degree\text{.}\) Tangens (2) 007n - Sinus, cosinus en tangens - basis - 0ms b Tangens in \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) geeft \(\tan(\angle K)={L\kern{-.8pt}M \over K\kern{-.8pt}L}\) ofwel \(\tan(59\degree)={48 \over K\kern{-.8pt}L}\text{.}\) 1p ○ Hieruit volgt \(K\kern{-.8pt}L={48 \over \tan(59\degree)}\text{.}\) 1p ○ Dus \(K\kern{-.8pt}L≈28{,}8\text{.}\) 1p 3p c Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(A\kern{-.8pt}C=26\text{,}\) \(A\kern{-.8pt}B=54\) en \(\angle A=90\degree\text{.}\) Tangens (3) 007o - Sinus, cosinus en tangens - basis - 0ms c Tangens in \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) geeft \(\tan(\angle C)={A\kern{-.8pt}B \over A\kern{-.8pt}C}\) ofwel \(\tan(\angle C)={54 \over 26}\text{.}\) 1p ○ Hieruit volgt \(\angle C=\tan^{-1}({54 \over 26})\text{.}\) 1p ○ Dus \(\angle C≈64{,}3\degree\text{.}\) 1p |
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| 3 havo | 6.4 De sinus en de cosinus |
opgave 13p a Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(P\kern{-.8pt}R=74\text{,}\) \(\angle P=47\degree\) en \(\angle Q=90\degree\text{.}\) Sinus (1) 007g - Sinus, cosinus en tangens - basis - 0ms a Sinus in \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) geeft \(\sin(\angle P)={Q\kern{-.8pt}R \over P\kern{-.8pt}R}\) ofwel \(\sin(47\degree)={Q\kern{-.8pt}R \over 74}\text{.}\) 1p ○ Hieruit volgt \(Q\kern{-.8pt}R=74⋅\sin(47\degree)\text{.}\) 1p ○ Dus \(Q\kern{-.8pt}R≈54{,}1\text{.}\) 1p 3p b Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(P\kern{-.8pt}Q=45\text{,}\) \(\angle R=36\degree\) en \(\angle P=90\degree\text{.}\) Sinus (2) 007h - Sinus, cosinus en tangens - basis - 0ms b Sinus in \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) geeft \(\sin(\angle R)={P\kern{-.8pt}Q \over Q\kern{-.8pt}R}\) ofwel \(\sin(36\degree)={45 \over Q\kern{-.8pt}R}\text{.}\) 1p ○ Hieruit volgt \(Q\kern{-.8pt}R={45 \over \sin(36\degree)}\text{.}\) 1p ○ Dus \(Q\kern{-.8pt}R≈76{,}6\text{.}\) 1p 3p c Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(A\kern{-.8pt}C=45\text{,}\) \(A\kern{-.8pt}B=61\) 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 \(\sin(\angle B)={45 \over 61}\text{.}\) 1p ○ Hieruit volgt \(\angle B=\sin^{-1}({45 \over 61})\text{.}\) 1p ○ Dus \(\angle B≈47{,}5\degree\text{.}\) 1p 3p d Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(A\kern{-.8pt}C=41\text{,}\) \(\angle A=44\degree\) en \(\angle B=90\degree\text{.}\) Cosinus (1) 007j - Sinus, cosinus en tangens - basis - 0ms d Cosinus in \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) geeft \(\cos(\angle A)={A\kern{-.8pt}B \over A\kern{-.8pt}C}\) ofwel \(\cos(44\degree)={A\kern{-.8pt}B \over 41}\text{.}\) 1p ○ Hieruit volgt \(A\kern{-.8pt}B=41⋅\cos(44\degree)\text{.}\) 1p ○ Dus \(A\kern{-.8pt}B≈29{,}5\text{.}\) 1p opgave 23p a Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(P\kern{-.8pt}R=54\text{,}\) \(\angle R=53\degree\) 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 \(\cos(53\degree)={54 \over Q\kern{-.8pt}R}\text{.}\) 1p ○ Hieruit volgt \(Q\kern{-.8pt}R={54 \over \cos(53\degree)}\text{.}\) 1p ○ Dus \(Q\kern{-.8pt}R≈89{,}7\text{.}\) 1p 3p b Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(P\kern{-.8pt}R=56\text{,}\) \(Q\kern{-.8pt}R=64\) en \(\angle P=90\degree\text{.}\) Cosinus (3) 007l - Sinus, cosinus en tangens - basis - 0ms b Cosinus in \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) geeft \(\cos(\angle R)={P\kern{-.8pt}R \over Q\kern{-.8pt}R}\) ofwel \(\cos(\angle R)={56 \over 64}\text{.}\) 1p ○ Hieruit volgt \(\angle R=\cos^{-1}({56 \over 64})\text{.}\) 1p ○ Dus \(\angle R≈29{,}0\degree\text{.}\) 1p |