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 \(Q\kern{-.8pt}R=55\text{,}\) \(\angle Q=33\degree\) 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 \(\tan(33\degree)={P\kern{-.8pt}R \over 55}\text{.}\) 1p ○ Hieruit volgt \(P\kern{-.8pt}R=55⋅\tan(33\degree)\text{.}\) 1p ○ Dus \(P\kern{-.8pt}R≈35{,}7\text{.}\) 1p 3p b Gegeven is \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) met \(K\kern{-.8pt}M=51\text{,}\) \(\angle L=47\degree\) 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 \(\tan(47\degree)={51 \over L\kern{-.8pt}M}\text{.}\) 1p ○ Hieruit volgt \(L\kern{-.8pt}M={51 \over \tan(47\degree)}\text{.}\) 1p ○ Dus \(L\kern{-.8pt}M≈47{,}6\text{.}\) 1p 3p c Gegeven is \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) met \(K\kern{-.8pt}M=52\text{,}\) \(K\kern{-.8pt}L=39\) en \(\angle K=90\degree\text{.}\) Tangens (3) 007o - Sinus, cosinus en tangens - basis - 0ms c Tangens in \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) geeft \(\tan(\angle M)={K\kern{-.8pt}L \over K\kern{-.8pt}M}\) ofwel \(\tan(\angle M)={39 \over 52}\text{.}\) 1p ○ Hieruit volgt \(\angle M=\tan^{-1}({39 \over 52})\text{.}\) 1p ○ Dus \(\angle M≈36{,}9\degree\text{.}\) 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 \(A\kern{-.8pt}B=59\text{,}\) \(\angle B=47\degree\) en \(\angle C=90\degree\text{.}\) Sinus (1) 007g - Sinus, cosinus en tangens - basis - 0ms a Sinus in \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) geeft \(\sin(\angle B)={A\kern{-.8pt}C \over A\kern{-.8pt}B}\) ofwel \(\sin(47\degree)={A\kern{-.8pt}C \over 59}\text{.}\) 1p ○ Hieruit volgt \(A\kern{-.8pt}C=59⋅\sin(47\degree)\text{.}\) 1p ○ Dus \(A\kern{-.8pt}C≈43{,}1\text{.}\) 1p 3p b Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(B\kern{-.8pt}C=55\text{,}\) \(\angle A=36\degree\) en \(\angle B=90\degree\text{.}\) Sinus (2) 007h - Sinus, cosinus en tangens - basis - 0ms b Sinus in \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) geeft \(\sin(\angle A)={B\kern{-.8pt}C \over A\kern{-.8pt}C}\) ofwel \(\sin(36\degree)={55 \over A\kern{-.8pt}C}\text{.}\) 1p ○ Hieruit volgt \(A\kern{-.8pt}C={55 \over \sin(36\degree)}\text{.}\) 1p ○ Dus \(A\kern{-.8pt}C≈93{,}6\text{.}\) 1p 3p c Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(A\kern{-.8pt}C=58\text{,}\) \(A\kern{-.8pt}B=83\) 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 \(\sin(\angle B)={58 \over 83}\text{.}\) 1p ○ Hieruit volgt \(\angle B=\sin^{-1}({58 \over 83})\text{.}\) 1p ○ Dus \(\angle B≈44{,}3\degree\text{.}\) 1p 3p d Gegeven is \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) met \(K\kern{-.8pt}M=65\text{,}\) \(\angle K=31\degree\) en \(\angle L=90\degree\text{.}\) Cosinus (1) 007j - Sinus, cosinus en tangens - basis - 0ms d Cosinus in \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) geeft \(\cos(\angle K)={K\kern{-.8pt}L \over K\kern{-.8pt}M}\) ofwel \(\cos(31\degree)={K\kern{-.8pt}L \over 65}\text{.}\) 1p ○ Hieruit volgt \(K\kern{-.8pt}L=65⋅\cos(31\degree)\text{.}\) 1p ○ Dus \(K\kern{-.8pt}L≈55{,}7\text{.}\) 1p opgave 23p a Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(Q\kern{-.8pt}R=42\text{,}\) \(\angle Q=39\degree\) 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 \(\cos(39\degree)={42 \over P\kern{-.8pt}Q}\text{.}\) 1p ○ Hieruit volgt \(P\kern{-.8pt}Q={42 \over \cos(39\degree)}\text{.}\) 1p ○ Dus \(P\kern{-.8pt}Q≈54{,}0\text{.}\) 1p 3p b Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(P\kern{-.8pt}R=27\text{,}\) \(Q\kern{-.8pt}R=66\) en \(\angle P=90\degree\text{.}\) Cosinus (3) 007l - Sinus, cosinus en tangens - basis - 0ms b Cosinus in \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) geeft \(\cos(\angle R)={P\kern{-.8pt}R \over Q\kern{-.8pt}R}\) ofwel \(\cos(\angle R)={27 \over 66}\text{.}\) 1p ○ Hieruit volgt \(\angle R=\cos^{-1}({27 \over 66})\text{.}\) 1p ○ Dus \(\angle R≈65{,}9\degree\text{.}\) 1p |