Getal & Ruimte (13e editie) - 3 havo
'Sinus, cosinus en tangens'.
| 3 havo | 6.3 Berekeningen met de tangens |
opgave 13p a Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(P\kern{-.8pt}Q = 60 \text{,}\) \(\angle P = 55\degree\) en \(\angle Q = 90\degree \text{.}\) Tangens (1) 007m - Sinus, cosinus en tangens - basis - 0ms a Tangens in \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) geeft \(\tan(\angle P) = {Q\kern{-.8pt}R \over P\kern{-.8pt}Q}\) ofwel \(\tan(55\degree) = {Q\kern{-.8pt}R \over 60} \text{.}\) 1p ○ Hieruit volgt \(Q\kern{-.8pt}R = 60 ⋅ \tan(55\degree) \text{.}\) 1p ○ Dus \(Q\kern{-.8pt}R ≈ 85{,}7 \text{.}\) 1p 3p b Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(Q\kern{-.8pt}R = 20 \text{,}\) \(\angle P = 46\degree\) 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 \(\tan(46\degree) = {20 \over P\kern{-.8pt}Q} \text{.}\) 1p ○ Hieruit volgt \(P\kern{-.8pt}Q = {20 \over \tan(46\degree)} \text{.}\) 1p ○ Dus \(P\kern{-.8pt}Q ≈ 19{,}3 \text{.}\) 1p 3p c Gegeven is \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) met \(K\kern{-.8pt}L = 36 \text{,}\) \(L\kern{-.8pt}M = 40\) 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 \(\tan(\angle K) = {40 \over 36} \text{.}\) 1p ○ Hieruit volgt \(\angle K = \tan^{-1}({40 \over 36}) \text{.}\) 1p ○ Dus \(\angle K ≈ 48{,}0\degree \text{.}\) 1p |
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| 3 havo | 6.4 De sinus en de cosinus |
opgave 13p a Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(Q\kern{-.8pt}R = 56 \text{,}\) \(\angle R = 38\degree\) en \(\angle P = 90\degree \text{.}\) Sinus (1) 007g - Sinus, cosinus en tangens - basis - 0ms a Sinus in \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) geeft \(\sin(\angle R) = {P\kern{-.8pt}Q \over Q\kern{-.8pt}R}\) ofwel \(\sin(38\degree) = {P\kern{-.8pt}Q \over 56} \text{.}\) 1p ○ Hieruit volgt \(P\kern{-.8pt}Q = 56 ⋅ \sin(38\degree) \text{.}\) 1p ○ Dus \(P\kern{-.8pt}Q ≈ 34{,}5 \text{.}\) 1p 3p b Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(P\kern{-.8pt}R = 60 \text{,}\) \(\angle Q = 37\degree\) en \(\angle R = 90\degree \text{.}\) Sinus (2) 007h - Sinus, cosinus en tangens - basis - 0ms b Sinus in \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) geeft \(\sin(\angle Q) = {P\kern{-.8pt}R \over P\kern{-.8pt}Q}\) ofwel \(\sin(37\degree) = {60 \over P\kern{-.8pt}Q} \text{.}\) 1p ○ Hieruit volgt \(P\kern{-.8pt}Q = {60 \over \sin(37\degree)} \text{.}\) 1p ○ Dus \(P\kern{-.8pt}Q ≈ 99{,}7 \text{.}\) 1p 3p c Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(A\kern{-.8pt}C = 33 \text{,}\) \(A\kern{-.8pt}B = 43\) en \(\angle C = 90\degree \text{.}\) Sinus (3) 007i - Sinus, cosinus en tangens - basis - 0ms c Sinus in \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) geeft \(\sin(\angle B) = {A\kern{-.8pt}C \over A\kern{-.8pt}B}\) ofwel \(\sin(\angle B) = {33 \over 43} \text{.}\) 1p ○ Hieruit volgt \(\angle B = \sin^{-1}({33 \over 43}) \text{.}\) 1p ○ Dus \(\angle B ≈ 50{,}1\degree \text{.}\) 1p 3p d Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(B\kern{-.8pt}C = 76 \text{,}\) \(\angle C = 43\degree\) en \(\angle A = 90\degree \text{.}\) Cosinus (1) 007j - Sinus, cosinus en tangens - basis - 0ms d Cosinus in \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) geeft \(\cos(\angle C) = {A\kern{-.8pt}C \over B\kern{-.8pt}C}\) ofwel \(\cos(43\degree) = {A\kern{-.8pt}C \over 76} \text{.}\) 1p ○ Hieruit volgt \(A\kern{-.8pt}C = 76 ⋅ \cos(43\degree) \text{.}\) 1p ○ Dus \(A\kern{-.8pt}C ≈ 55{,}6 \text{.}\) 1p opgave 23p a Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(Q\kern{-.8pt}R = 28 \text{,}\) \(\angle Q = 50\degree\) en \(\angle R = 90\degree \text{.}\) Cosinus (2) 007k - Sinus, cosinus en tangens - basis - 0ms a Cosinus in \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) geeft \(\cos(\angle Q) = {Q\kern{-.8pt}R \over P\kern{-.8pt}Q}\) ofwel \(\cos(50\degree) = {28 \over P\kern{-.8pt}Q} \text{.}\) 1p ○ Hieruit volgt \(P\kern{-.8pt}Q = {28 \over \cos(50\degree)} \text{.}\) 1p ○ Dus \(P\kern{-.8pt}Q ≈ 43{,}6 \text{.}\) 1p 3p b Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(A\kern{-.8pt}B = 57 \text{,}\) \(A\kern{-.8pt}C = 73\) en \(\angle B = 90\degree \text{.}\) Cosinus (3) 007l - Sinus, cosinus en tangens - basis - 0ms b Cosinus in \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) geeft \(\cos(\angle A) = {A\kern{-.8pt}B \over A\kern{-.8pt}C}\) ofwel \(\cos(\angle A) = {57 \over 73} \text{.}\) 1p ○ Hieruit volgt \(\angle A = \cos^{-1}({57 \over 73}) \text{.}\) 1p ○ Dus \(\angle A ≈ 38{,}7\degree \text{.}\) 1p |