Getal & Ruimte (12e editie) - havo wiskunde B
'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 \(Q\kern{-.8pt}R = 51 \text{,}\) \(\angle Q = 42\degree\) 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 \(\tan(42\degree) = {P\kern{-.8pt}R \over 51} \text{.}\) 1p ○ Hieruit volgt \(P\kern{-.8pt}R = 51 ⋅ \tan(42\degree) \text{.}\) 1p ○ Dus \(P\kern{-.8pt}R ≈ 45{,}9 \text{.}\) 1p 3p b Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(P\kern{-.8pt}R = 60 \text{,}\) \(\angle Q = 31\degree\) en \(\angle R = 90\degree \text{.}\) Tangens (2) 007n - Sinus, cosinus en tangens - basis - 0ms b Tangens in \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) geeft \(\tan(\angle Q) = {P\kern{-.8pt}R \over Q\kern{-.8pt}R}\) ofwel \(\tan(31\degree) = {60 \over Q\kern{-.8pt}R} \text{.}\) 1p ○ Hieruit volgt \(Q\kern{-.8pt}R = {60 \over \tan(31\degree)} \text{.}\) 1p ○ Dus \(Q\kern{-.8pt}R ≈ 99{,}9 \text{.}\) 1p 3p c Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(A\kern{-.8pt}C = 56 \text{,}\) \(A\kern{-.8pt}B = 58\) 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 \(\tan(\angle C) = {58 \over 56} \text{.}\) 1p ○ Hieruit volgt \(\angle C = \tan^{-1}({58 \over 56}) \text{.}\) 1p ○ Dus \(\angle C ≈ 46{,}0\degree \text{.}\) 1p |
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| 3 havo | 6.4 De sinus en de cosinus |
opgave 13p a Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(B\kern{-.8pt}C = 49 \text{,}\) \(\angle C = 57\degree\) en \(\angle A = 90\degree \text{.}\) Sinus (1) 007g - Sinus, cosinus en tangens - basis - 0ms a Sinus in \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) geeft \(\sin(\angle C) = {A\kern{-.8pt}B \over B\kern{-.8pt}C}\) ofwel \(\sin(57\degree) = {A\kern{-.8pt}B \over 49} \text{.}\) 1p ○ Hieruit volgt \(A\kern{-.8pt}B = 49 ⋅ \sin(57\degree) \text{.}\) 1p ○ Dus \(A\kern{-.8pt}B ≈ 41{,}1 \text{.}\) 1p 3p b Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(A\kern{-.8pt}C = 23 \text{,}\) \(\angle B = 38\degree\) en \(\angle C = 90\degree \text{.}\) Sinus (2) 007h - Sinus, cosinus en tangens - basis - 0ms b Sinus in \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) geeft \(\sin(\angle B) = {A\kern{-.8pt}C \over A\kern{-.8pt}B}\) ofwel \(\sin(38\degree) = {23 \over A\kern{-.8pt}B} \text{.}\) 1p ○ Hieruit volgt \(A\kern{-.8pt}B = {23 \over \sin(38\degree)} \text{.}\) 1p ○ Dus \(A\kern{-.8pt}B ≈ 37{,}4 \text{.}\) 1p 3p c Gegeven is \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) met \(K\kern{-.8pt}L = 37 \text{,}\) \(L\kern{-.8pt}M = 43\) 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 \(\sin(\angle M) = {37 \over 43} \text{.}\) 1p ○ Hieruit volgt \(\angle M = \sin^{-1}({37 \over 43}) \text{.}\) 1p ○ Dus \(\angle M ≈ 59{,}4\degree \text{.}\) 1p 3p d Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(Q\kern{-.8pt}R = 73 \text{,}\) \(\angle R = 54\degree\) 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 \(\cos(54\degree) = {P\kern{-.8pt}R \over 73} \text{.}\) 1p ○ Hieruit volgt \(P\kern{-.8pt}R = 73 ⋅ \cos(54\degree) \text{.}\) 1p ○ Dus \(P\kern{-.8pt}R ≈ 42{,}9 \text{.}\) 1p opgave 23p a Gegeven is \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) met \(K\kern{-.8pt}L = 22 \text{,}\) \(\angle K = 49\degree\) 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 \(\cos(49\degree) = {22 \over K\kern{-.8pt}M} \text{.}\) 1p ○ Hieruit volgt \(K\kern{-.8pt}M = {22 \over \cos(49\degree)} \text{.}\) 1p ○ Dus \(K\kern{-.8pt}M ≈ 33{,}5 \text{.}\) 1p 3p b Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(B\kern{-.8pt}C = 49 \text{,}\) \(A\kern{-.8pt}B = 53\) 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 \(\cos(\angle B) = {49 \over 53} \text{.}\) 1p ○ Hieruit volgt \(\angle B = \cos^{-1}({49 \over 53}) \text{.}\) 1p ○ Dus \(\angle B ≈ 22{,}4\degree \text{.}\) 1p |