Getal & Ruimte (13e editie) - vwo wiskunde B
'Sinus, cosinus en tangens'.
| 3 vwo | 6.3 Berekeningen met de tangens |
opgave 13p a Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(P\kern{-.8pt}R = 21 \text{,}\) \(\angle R = 59\degree\) 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 \(\tan(59\degree) = {P\kern{-.8pt}Q \over 21} \text{.}\) 1p ○ Hieruit volgt \(P\kern{-.8pt}Q = 21 ⋅ \tan(59\degree) \text{.}\) 1p ○ Dus \(P\kern{-.8pt}Q ≈ 34{,}9 \text{.}\) 1p 3p b Gegeven is \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) met \(K\kern{-.8pt}M = 41 \text{,}\) \(\angle L = 57\degree\) en \(\angle M = 90\degree \text{.}\) Tangens (2) 007n - Sinus, cosinus en tangens - basis - 0ms b Tangens in \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) geeft \(\tan(\angle L) = {K\kern{-.8pt}M \over L\kern{-.8pt}M}\) ofwel \(\tan(57\degree) = {41 \over L\kern{-.8pt}M} \text{.}\) 1p ○ Hieruit volgt \(L\kern{-.8pt}M = {41 \over \tan(57\degree)} \text{.}\) 1p ○ Dus \(L\kern{-.8pt}M ≈ 26{,}6 \text{.}\) 1p 3p c Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(A\kern{-.8pt}B = 46 \text{,}\) \(B\kern{-.8pt}C = 36\) en \(\angle B = 90\degree \text{.}\) Tangens (3) 007o - Sinus, cosinus en tangens - basis - 0ms c Tangens in \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) geeft \(\tan(\angle A) = {B\kern{-.8pt}C \over A\kern{-.8pt}B}\) ofwel \(\tan(\angle A) = {36 \over 46} \text{.}\) 1p ○ Hieruit volgt \(\angle A = \tan^{-1}({36 \over 46}) \text{.}\) 1p ○ Dus \(\angle A ≈ 38{,}0\degree \text{.}\) 1p |
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| 3 vwo | 6.4 De sinus en de cosinus |
opgave 13p a Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(A\kern{-.8pt}C = 48 \text{,}\) \(\angle A = 40\degree\) en \(\angle B = 90\degree \text{.}\) Sinus (1) 007g - Sinus, cosinus en tangens - basis - 0ms a Sinus in \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) geeft \(\sin(\angle A) = {B\kern{-.8pt}C \over A\kern{-.8pt}C}\) ofwel \(\sin(40\degree) = {B\kern{-.8pt}C \over 48} \text{.}\) 1p ○ Hieruit volgt \(B\kern{-.8pt}C = 48 ⋅ \sin(40\degree) \text{.}\) 1p ○ Dus \(B\kern{-.8pt}C ≈ 30{,}9 \text{.}\) 1p 3p b Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(A\kern{-.8pt}B = 37 \text{,}\) \(\angle C = 35\degree\) en \(\angle A = 90\degree \text{.}\) Sinus (2) 007h - Sinus, cosinus en tangens - basis - 0ms b Sinus in \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) geeft \(\sin(\angle C) = {A\kern{-.8pt}B \over B\kern{-.8pt}C}\) ofwel \(\sin(35\degree) = {37 \over B\kern{-.8pt}C} \text{.}\) 1p ○ Hieruit volgt \(B\kern{-.8pt}C = {37 \over \sin(35\degree)} \text{.}\) 1p ○ Dus \(B\kern{-.8pt}C ≈ 64{,}5 \text{.}\) 1p 3p c Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(P\kern{-.8pt}R = 53 \text{,}\) \(P\kern{-.8pt}Q = 70\) 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 \(\sin(\angle Q) = {53 \over 70} \text{.}\) 1p ○ Hieruit volgt \(\angle Q = \sin^{-1}({53 \over 70}) \text{.}\) 1p ○ Dus \(\angle Q ≈ 49{,}2\degree \text{.}\) 1p 3p d Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(A\kern{-.8pt}C = 64 \text{,}\) \(\angle A = 34\degree\) 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 \(\cos(34\degree) = {A\kern{-.8pt}B \over 64} \text{.}\) 1p ○ Hieruit volgt \(A\kern{-.8pt}B = 64 ⋅ \cos(34\degree) \text{.}\) 1p ○ Dus \(A\kern{-.8pt}B ≈ 53{,}1 \text{.}\) 1p opgave 23p a Gegeven is \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) met \(K\kern{-.8pt}L = 25 \text{,}\) \(\angle K = 36\degree\) 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 \(\cos(36\degree) = {25 \over K\kern{-.8pt}M} \text{.}\) 1p ○ Hieruit volgt \(K\kern{-.8pt}M = {25 \over \cos(36\degree)} \text{.}\) 1p ○ Dus \(K\kern{-.8pt}M ≈ 30{,}9 \text{.}\) 1p 3p b Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(B\kern{-.8pt}C = 55 \text{,}\) \(A\kern{-.8pt}B = 65\) en \(\angle C = 90\degree \text{.}\) Cosinus (3) 007l - Sinus, cosinus en tangens - basis - 0ms b Cosinus in \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) geeft \(\cos(\angle B) = {B\kern{-.8pt}C \over A\kern{-.8pt}B}\) ofwel \(\cos(\angle B) = {55 \over 65} \text{.}\) 1p ○ Hieruit volgt \(\angle B = \cos^{-1}({55 \over 65}) \text{.}\) 1p ○ Dus \(\angle B ≈ 32{,}2\degree \text{.}\) 1p |