Getal & Ruimte (12e editie) - havo wiskunde B
'Sinus, cosinus en tangens'.
| 3 havo | 6.3 Berekeningen met de tangens |
opgave 13p a Gegeven is \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) met \(K\kern{-.8pt}L=44\text{,}\) \(\angle K=56\degree\) en \(\angle L=90\degree\text{.}\) Tangens (1) 007m - Sinus, cosinus en tangens - basis a Tangens in \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) geeft \(\tan(\angle K)={L\kern{-.8pt}M \over K\kern{-.8pt}L}\) ofwel \(\tan(56\degree)={L\kern{-.8pt}M \over 44}\text{.}\) 1p ○ Hieruit volgt \(L\kern{-.8pt}M=44⋅\tan(56\degree)\text{.}\) 1p ○ Dus \(L\kern{-.8pt}M≈65{,}2\text{.}\) 1p 3p b Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(Q\kern{-.8pt}R=52\text{,}\) \(\angle P=52\degree\) en \(\angle Q=90\degree\text{.}\) Tangens (2) 007n - Sinus, cosinus en tangens - basis 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 \(\tan(52\degree)={52 \over P\kern{-.8pt}Q}\text{.}\) 1p ○ Hieruit volgt \(P\kern{-.8pt}Q={52 \over \tan(52\degree)}\text{.}\) 1p ○ Dus \(P\kern{-.8pt}Q≈40{,}6\text{.}\) 1p 3p c Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(Q\kern{-.8pt}R=27\text{,}\) \(P\kern{-.8pt}R=32\) en \(\angle R=90\degree\text{.}\) Tangens (3) 007o - Sinus, cosinus en tangens - basis c Tangens in \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) geeft \(\tan(\angle Q)={P\kern{-.8pt}R \over Q\kern{-.8pt}R}\) ofwel \(\tan(\angle Q)={32 \over 27}\text{.}\) 1p ○ Hieruit volgt \(\angle Q=\tan^{-1}({32 \over 27})\text{.}\) 1p ○ Dus \(\angle Q≈49{,}8\degree\text{.}\) 1p |
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| 3 havo | 6.4 De sinus en de cosinus |
opgave 13p a Gegeven is \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) met \(L\kern{-.8pt}M=66\text{,}\) \(\angle M=42\degree\) en \(\angle K=90\degree\text{.}\) Sinus (1) 007g - Sinus, cosinus en tangens - basis a Sinus in \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) geeft \(\sin(\angle M)={K\kern{-.8pt}L \over L\kern{-.8pt}M}\) ofwel \(\sin(42\degree)={K\kern{-.8pt}L \over 66}\text{.}\) 1p ○ Hieruit volgt \(K\kern{-.8pt}L=66⋅\sin(42\degree)\text{.}\) 1p ○ Dus \(K\kern{-.8pt}L≈44{,}2\text{.}\) 1p 3p b Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(P\kern{-.8pt}Q=40\text{,}\) \(\angle R=54\degree\) 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 \(\sin(54\degree)={40 \over Q\kern{-.8pt}R}\text{.}\) 1p ○ Hieruit volgt \(Q\kern{-.8pt}R={40 \over \sin(54\degree)}\text{.}\) 1p ○ Dus \(Q\kern{-.8pt}R≈49{,}4\text{.}\) 1p 3p c Gegeven is \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) met \(K\kern{-.8pt}L=38\text{,}\) \(L\kern{-.8pt}M=58\) en \(\angle K=90\degree\text{.}\) Sinus (3) 007i - Sinus, cosinus en tangens - basis 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 \(\sin(\angle M)={38 \over 58}\text{.}\) 1p ○ Hieruit volgt \(\angle M=\sin^{-1}({38 \over 58})\text{.}\) 1p ○ Dus \(\angle M≈40{,}9\degree\text{.}\) 1p 3p d Gegeven is \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) met \(L\kern{-.8pt}M=76\text{,}\) \(\angle M=40\degree\) en \(\angle K=90\degree\text{.}\) Cosinus (1) 007j - Sinus, cosinus en tangens - basis d Cosinus in \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) geeft \(\cos(\angle M)={K\kern{-.8pt}M \over L\kern{-.8pt}M}\) ofwel \(\cos(40\degree)={K\kern{-.8pt}M \over 76}\text{.}\) 1p ○ Hieruit volgt \(K\kern{-.8pt}M=76⋅\cos(40\degree)\text{.}\) 1p ○ Dus \(K\kern{-.8pt}M≈58{,}2\text{.}\) 1p opgave 23p a Gegeven is \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) met \(L\kern{-.8pt}M=45\text{,}\) \(\angle L=53\degree\) en \(\angle M=90\degree\text{.}\) Cosinus (2) 007k - Sinus, cosinus en tangens - basis 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 \(\cos(53\degree)={45 \over K\kern{-.8pt}L}\text{.}\) 1p ○ Hieruit volgt \(K\kern{-.8pt}L={45 \over \cos(53\degree)}\text{.}\) 1p ○ Dus \(K\kern{-.8pt}L≈74{,}8\text{.}\) 1p 3p b Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(P\kern{-.8pt}Q=37\text{,}\) \(P\kern{-.8pt}R=51\) en \(\angle Q=90\degree\text{.}\) Cosinus (3) 007l - Sinus, cosinus en tangens - basis b Cosinus in \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) geeft \(\cos(\angle P)={P\kern{-.8pt}Q \over P\kern{-.8pt}R}\) ofwel \(\cos(\angle P)={37 \over 51}\text{.}\) 1p ○ Hieruit volgt \(\angle P=\cos^{-1}({37 \over 51})\text{.}\) 1p ○ Dus \(\angle P≈43{,}5\degree\text{.}\) 1p |