Getal & Ruimte (12e editie) - vwo wiskunde B
'Sinus, cosinus en tangens'.
| 3 vwo | 6.3 Berekeningen met de tangens |
opgave 13p a Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(Q\kern{-.8pt}R = 43 \text{,}\) \(\angle Q = 40\degree\) en \(\angle R = 90\degree \text{.}\) Tangens (1) 007m - Sinus, cosinus en tangens - basis - 0ms a Tangens in \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) geeft \(\tan(\angle Q) = {P\kern{-.8pt}R \over Q\kern{-.8pt}R}\) ofwel \(\tan(40\degree) = {P\kern{-.8pt}R \over 43} \text{.}\) 1p ○ Hieruit volgt \(P\kern{-.8pt}R = 43 ⋅ \tan(40\degree) \text{.}\) 1p ○ Dus \(P\kern{-.8pt}R ≈ 36{,}1 \text{.}\) 1p 3p b Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(A\kern{-.8pt}C = 39 \text{,}\) \(\angle B = 55\degree\) en \(\angle C = 90\degree \text{.}\) Tangens (2) 007n - Sinus, cosinus en tangens - basis - 0ms b Tangens in \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) geeft \(\tan(\angle B) = {A\kern{-.8pt}C \over B\kern{-.8pt}C}\) ofwel \(\tan(55\degree) = {39 \over B\kern{-.8pt}C} \text{.}\) 1p ○ Hieruit volgt \(B\kern{-.8pt}C = {39 \over \tan(55\degree)} \text{.}\) 1p ○ Dus \(B\kern{-.8pt}C ≈ 27{,}3 \text{.}\) 1p 3p c Gegeven is \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) met \(K\kern{-.8pt}L = 35 \text{,}\) \(L\kern{-.8pt}M = 29\) en \(\angle L = 90\degree \text{.}\) Tangens (3) 007o - Sinus, cosinus en tangens - basis - 0ms c Tangens in \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) geeft \(\tan(\angle K) = {L\kern{-.8pt}M \over K\kern{-.8pt}L}\) ofwel \(\tan(\angle K) = {29 \over 35} \text{.}\) 1p ○ Hieruit volgt \(\angle K = \tan^{-1}({29 \over 35}) \text{.}\) 1p ○ Dus \(\angle K ≈ 39{,}6\degree \text{.}\) 1p |
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| 3 vwo | 6.4 De sinus en de cosinus |
opgave 13p a Gegeven is \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) met \(L\kern{-.8pt}M = 77 \text{,}\) \(\angle M = 50\degree\) en \(\angle K = 90\degree \text{.}\) Sinus (1) 007g - Sinus, cosinus en tangens - basis - 0ms 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 \(\sin(50\degree) = {K\kern{-.8pt}L \over 77} \text{.}\) 1p ○ Hieruit volgt \(K\kern{-.8pt}L = 77 ⋅ \sin(50\degree) \text{.}\) 1p ○ Dus \(K\kern{-.8pt}L ≈ 59{,}0 \text{.}\) 1p 3p b Gegeven is \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) met \(L\kern{-.8pt}M = 20 \text{,}\) \(\angle K = 44\degree\) en \(\angle L = 90\degree \text{.}\) Sinus (2) 007h - Sinus, cosinus en tangens - basis - 0ms b Sinus in \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) geeft \(\sin(\angle K) = {L\kern{-.8pt}M \over K\kern{-.8pt}M}\) ofwel \(\sin(44\degree) = {20 \over K\kern{-.8pt}M} \text{.}\) 1p ○ Hieruit volgt \(K\kern{-.8pt}M = {20 \over \sin(44\degree)} \text{.}\) 1p ○ Dus \(K\kern{-.8pt}M ≈ 28{,}8 \text{.}\) 1p 3p c Gegeven is \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) met \(K\kern{-.8pt}L = 23 \text{,}\) \(L\kern{-.8pt}M = 52\) 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 \(\sin(\angle M) = {23 \over 52} \text{.}\) 1p ○ Hieruit volgt \(\angle M = \sin^{-1}({23 \over 52}) \text{.}\) 1p ○ Dus \(\angle M ≈ 26{,}3\degree \text{.}\) 1p 3p d Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(A\kern{-.8pt}B = 78 \text{,}\) \(\angle B = 53\degree\) en \(\angle C = 90\degree \text{.}\) Cosinus (1) 007j - Sinus, cosinus en tangens - basis - 0ms d Cosinus in \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) geeft \(\cos(\angle B) = {B\kern{-.8pt}C \over A\kern{-.8pt}B}\) ofwel \(\cos(53\degree) = {B\kern{-.8pt}C \over 78} \text{.}\) 1p ○ Hieruit volgt \(B\kern{-.8pt}C = 78 ⋅ \cos(53\degree) \text{.}\) 1p ○ Dus \(B\kern{-.8pt}C ≈ 46{,}9 \text{.}\) 1p opgave 23p a Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(P\kern{-.8pt}Q = 20 \text{,}\) \(\angle P = 58\degree\) en \(\angle Q = 90\degree \text{.}\) Cosinus (2) 007k - Sinus, cosinus en tangens - basis - 0ms a Cosinus in \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) geeft \(\cos(\angle P) = {P\kern{-.8pt}Q \over P\kern{-.8pt}R}\) ofwel \(\cos(58\degree) = {20 \over P\kern{-.8pt}R} \text{.}\) 1p ○ Hieruit volgt \(P\kern{-.8pt}R = {20 \over \cos(58\degree)} \text{.}\) 1p ○ Dus \(P\kern{-.8pt}R ≈ 37{,}7 \text{.}\) 1p 3p b Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(Q\kern{-.8pt}R = 41 \text{,}\) \(P\kern{-.8pt}Q = 56\) en \(\angle R = 90\degree \text{.}\) Cosinus (3) 007l - Sinus, cosinus en tangens - basis - 0ms b Cosinus in \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) geeft \(\cos(\angle Q) = {Q\kern{-.8pt}R \over P\kern{-.8pt}Q}\) ofwel \(\cos(\angle Q) = {41 \over 56} \text{.}\) 1p ○ Hieruit volgt \(\angle Q = \cos^{-1}({41 \over 56}) \text{.}\) 1p ○ Dus \(\angle Q ≈ 42{,}9\degree \text{.}\) 1p |