Getal & Ruimte (13e 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 \(L\kern{-.8pt}M=27\text{,}\) \(\angle L=35\degree\) 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 \(\tan(35\degree)={K\kern{-.8pt}M \over 27}\text{.}\) 1p ○ Hieruit volgt \(K\kern{-.8pt}M=27⋅\tan(35\degree)\text{.}\) 1p ○ Dus \(K\kern{-.8pt}M≈18{,}9\text{.}\) 1p 3p b Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(A\kern{-.8pt}B=22\text{,}\) \(\angle C=36\degree\) en \(\angle A=90\degree\text{.}\) Tangens (2) 007n - Sinus, cosinus en tangens - basis - 0ms b Tangens in \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) geeft \(\tan(\angle C)={A\kern{-.8pt}B \over A\kern{-.8pt}C}\) ofwel \(\tan(36\degree)={22 \over A\kern{-.8pt}C}\text{.}\) 1p ○ Hieruit volgt \(A\kern{-.8pt}C={22 \over \tan(36\degree)}\text{.}\) 1p ○ Dus \(A\kern{-.8pt}C≈30{,}3\text{.}\) 1p 3p c Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(A\kern{-.8pt}C=52\text{,}\) \(A\kern{-.8pt}B=26\) 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 \(\tan(\angle C)={26 \over 52}\text{.}\) 1p ○ Hieruit volgt \(\angle C=\tan^{-1}({26 \over 52})\text{.}\) 1p ○ Dus \(\angle C≈26{,}6\degree\text{.}\) 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 \(P\kern{-.8pt}Q=48\text{,}\) \(\angle Q=39\degree\) 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 \(\sin(39\degree)={P\kern{-.8pt}R \over 48}\text{.}\) 1p ○ Hieruit volgt \(P\kern{-.8pt}R=48⋅\sin(39\degree)\text{.}\) 1p ○ Dus \(P\kern{-.8pt}R≈30{,}2\text{.}\) 1p 3p b Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(B\kern{-.8pt}C=33\text{,}\) \(\angle A=55\degree\) en \(\angle B=90\degree\text{.}\) Sinus (2) 007h - Sinus, cosinus en tangens - basis - 0ms b Sinus in \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) geeft \(\sin(\angle A)={B\kern{-.8pt}C \over A\kern{-.8pt}C}\) ofwel \(\sin(55\degree)={33 \over A\kern{-.8pt}C}\text{.}\) 1p ○ Hieruit volgt \(A\kern{-.8pt}C={33 \over \sin(55\degree)}\text{.}\) 1p ○ Dus \(A\kern{-.8pt}C≈40{,}3\text{.}\) 1p 3p c Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(P\kern{-.8pt}R=38\text{,}\) \(P\kern{-.8pt}Q=56\) en \(\angle R=90\degree\text{.}\) Sinus (3) 007i - Sinus, cosinus en tangens - basis - 0ms 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 \(\sin(\angle Q)={38 \over 56}\text{.}\) 1p ○ Hieruit volgt \(\angle Q=\sin^{-1}({38 \over 56})\text{.}\) 1p ○ Dus \(\angle Q≈42{,}7\degree\text{.}\) 1p 3p d Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(P\kern{-.8pt}R=45\text{,}\) \(\angle P=32\degree\) en \(\angle Q=90\degree\text{.}\) Cosinus (1) 007j - Sinus, cosinus en tangens - basis - 0ms d Cosinus in \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) geeft \(\cos(\angle P)={P\kern{-.8pt}Q \over P\kern{-.8pt}R}\) ofwel \(\cos(32\degree)={P\kern{-.8pt}Q \over 45}\text{.}\) 1p ○ Hieruit volgt \(P\kern{-.8pt}Q=45⋅\cos(32\degree)\text{.}\) 1p ○ Dus \(P\kern{-.8pt}Q≈38{,}2\text{.}\) 1p opgave 23p a Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(A\kern{-.8pt}C=45\text{,}\) \(\angle C=55\degree\) en \(\angle A=90\degree\text{.}\) Cosinus (2) 007k - Sinus, cosinus en tangens - basis - 0ms a Cosinus in \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) geeft \(\cos(\angle C)={A\kern{-.8pt}C \over B\kern{-.8pt}C}\) ofwel \(\cos(55\degree)={45 \over B\kern{-.8pt}C}\text{.}\) 1p ○ Hieruit volgt \(B\kern{-.8pt}C={45 \over \cos(55\degree)}\text{.}\) 1p ○ Dus \(B\kern{-.8pt}C≈78{,}5\text{.}\) 1p 3p b Gegeven is \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) met \(K\kern{-.8pt}L=47\text{,}\) \(K\kern{-.8pt}M=65\) en \(\angle L=90\degree\text{.}\) Cosinus (3) 007l - Sinus, cosinus en tangens - basis - 1ms b Cosinus in \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) geeft \(\cos(\angle K)={K\kern{-.8pt}L \over K\kern{-.8pt}M}\) ofwel \(\cos(\angle K)={47 \over 65}\text{.}\) 1p ○ Hieruit volgt \(\angle K=\cos^{-1}({47 \over 65})\text{.}\) 1p ○ Dus \(\angle K≈43{,}7\degree\text{.}\) 1p |