Getal & Ruimte (12e editie) - vwo wiskunde B
'Sinus, cosinus en tangens'.
| 3 vwo | 6.3 Berekeningen met de tangens |
opgave 13p a Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(A\kern{-.8pt}B = 28 \text{,}\) \(\angle A = 40\degree\) en \(\angle B = 90\degree \text{.}\) Tangens (1) 007m - Sinus, cosinus en tangens - basis - 0ms a Tangens in \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) geeft \(\tan(\angle A) = {B\kern{-.8pt}C \over A\kern{-.8pt}B}\) ofwel \(\tan(40\degree) = {B\kern{-.8pt}C \over 28} \text{.}\) 1p ○ Hieruit volgt \(B\kern{-.8pt}C = 28 ⋅ \tan(40\degree) \text{.}\) 1p ○ Dus \(B\kern{-.8pt}C ≈ 23{,}5 \text{.}\) 1p 3p b Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(Q\kern{-.8pt}R = 53 \text{,}\) \(\angle P = 54\degree\) 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 \(\tan(54\degree) = {53 \over P\kern{-.8pt}Q} \text{.}\) 1p ○ Hieruit volgt \(P\kern{-.8pt}Q = {53 \over \tan(54\degree)} \text{.}\) 1p ○ Dus \(P\kern{-.8pt}Q ≈ 38{,}5 \text{.}\) 1p 3p c Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(A\kern{-.8pt}C = 45 \text{,}\) \(A\kern{-.8pt}B = 45\) 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 \(\tan(\angle C) = {45 \over 45} \text{.}\) 1p ○ Hieruit volgt \(\angle C = \tan^{-1}({45 \over 45}) \text{.}\) 1p ○ Dus \(\angle C = 45{,}0\degree \text{.}\) 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 \(K\kern{-.8pt}M = 63 \text{,}\) \(\angle K = 42\degree\) en \(\angle L = 90\degree \text{.}\) Sinus (1) 007g - Sinus, cosinus en tangens - basis - 0ms a Sinus in \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) geeft \(\sin(\angle K) = {L\kern{-.8pt}M \over K\kern{-.8pt}M}\) ofwel \(\sin(42\degree) = {L\kern{-.8pt}M \over 63} \text{.}\) 1p ○ Hieruit volgt \(L\kern{-.8pt}M = 63 ⋅ \sin(42\degree) \text{.}\) 1p ○ Dus \(L\kern{-.8pt}M ≈ 42{,}2 \text{.}\) 1p 3p b Gegeven is \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) met \(L\kern{-.8pt}M = 59 \text{,}\) \(\angle K = 49\degree\) 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 \(\sin(49\degree) = {59 \over K\kern{-.8pt}M} \text{.}\) 1p ○ Hieruit volgt \(K\kern{-.8pt}M = {59 \over \sin(49\degree)} \text{.}\) 1p ○ Dus \(K\kern{-.8pt}M ≈ 78{,}2 \text{.}\) 1p 3p c Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(Q\kern{-.8pt}R = 30 \text{,}\) \(P\kern{-.8pt}R = 64\) en \(\angle Q = 90\degree \text{.}\) Sinus (3) 007i - Sinus, cosinus en tangens - basis - 0ms c Sinus in \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) geeft \(\sin(\angle P) = {Q\kern{-.8pt}R \over P\kern{-.8pt}R}\) ofwel \(\sin(\angle P) = {30 \over 64} \text{.}\) 1p ○ Hieruit volgt \(\angle P = \sin^{-1}({30 \over 64}) \text{.}\) 1p ○ Dus \(\angle P ≈ 28{,}0\degree \text{.}\) 1p 3p d Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(Q\kern{-.8pt}R = 64 \text{,}\) \(\angle R = 47\degree\) en \(\angle P = 90\degree \text{.}\) Cosinus (1) 007j - Sinus, cosinus en tangens - basis - 0ms d Cosinus in \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) geeft \(\cos(\angle R) = {P\kern{-.8pt}R \over Q\kern{-.8pt}R}\) ofwel \(\cos(47\degree) = {P\kern{-.8pt}R \over 64} \text{.}\) 1p ○ Hieruit volgt \(P\kern{-.8pt}R = 64 ⋅ \cos(47\degree) \text{.}\) 1p ○ Dus \(P\kern{-.8pt}R ≈ 43{,}6 \text{.}\) 1p opgave 23p a Gegeven is \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) met \(K\kern{-.8pt}L = 45 \text{,}\) \(\angle K = 52\degree\) en \(\angle L = 90\degree \text{.}\) Cosinus (2) 007k - Sinus, cosinus en tangens - basis - 0ms a Cosinus in \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) geeft \(\cos(\angle K) = {K\kern{-.8pt}L \over K\kern{-.8pt}M}\) ofwel \(\cos(52\degree) = {45 \over K\kern{-.8pt}M} \text{.}\) 1p ○ Hieruit volgt \(K\kern{-.8pt}M = {45 \over \cos(52\degree)} \text{.}\) 1p ○ Dus \(K\kern{-.8pt}M ≈ 73{,}1 \text{.}\) 1p 3p b Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(P\kern{-.8pt}Q = 35 \text{,}\) \(P\kern{-.8pt}R = 59\) en \(\angle Q = 90\degree \text{.}\) Cosinus (3) 007l - Sinus, cosinus en tangens - basis - 0ms b Cosinus in \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) geeft \(\cos(\angle P) = {P\kern{-.8pt}Q \over P\kern{-.8pt}R}\) ofwel \(\cos(\angle P) = {35 \over 59} \text{.}\) 1p ○ Hieruit volgt \(\angle P = \cos^{-1}({35 \over 59}) \text{.}\) 1p ○ Dus \(\angle P ≈ 53{,}6\degree \text{.}\) 1p |