Getal & Ruimte (13e 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 \(P\kern{-.8pt}Q=29\text{,}\) \(\angle P=37\degree\) 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 \(\tan(37\degree)={Q\kern{-.8pt}R \over 29}\text{.}\) 1p ○ Hieruit volgt \(Q\kern{-.8pt}R=29⋅\tan(37\degree)\text{.}\) 1p ○ Dus \(Q\kern{-.8pt}R≈21{,}9\text{.}\) 1p 3p b Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(A\kern{-.8pt}C=53\text{,}\) \(\angle B=52\degree\) en \(\angle C=90\degree\text{.}\) Tangens (2) 007n - Sinus, cosinus en tangens - basis - 0ms b Tangens in \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) geeft \(\tan(\angle B)={A\kern{-.8pt}C \over B\kern{-.8pt}C}\) ofwel \(\tan(52\degree)={53 \over B\kern{-.8pt}C}\text{.}\) 1p ○ Hieruit volgt \(B\kern{-.8pt}C={53 \over \tan(52\degree)}\text{.}\) 1p ○ Dus \(B\kern{-.8pt}C≈41{,}4\text{.}\) 1p 3p c Gegeven is \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) met \(K\kern{-.8pt}L=24\text{,}\) \(L\kern{-.8pt}M=55\) 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 \(\tan(\angle K)={55 \over 24}\text{.}\) 1p ○ Hieruit volgt \(\angle K=\tan^{-1}({55 \over 24})\text{.}\) 1p ○ Dus \(\angle K≈66{,}4\degree\text{.}\) 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 \(A\kern{-.8pt}C=64\text{,}\) \(\angle A=47\degree\) 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 \(\sin(47\degree)={B\kern{-.8pt}C \over 64}\text{.}\) 1p ○ Hieruit volgt \(B\kern{-.8pt}C=64⋅\sin(47\degree)\text{.}\) 1p ○ Dus \(B\kern{-.8pt}C≈46{,}8\text{.}\) 1p 3p b Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(B\kern{-.8pt}C=35\text{,}\) \(\angle A=47\degree\) 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 \(\sin(47\degree)={35 \over A\kern{-.8pt}C}\text{.}\) 1p ○ Hieruit volgt \(A\kern{-.8pt}C={35 \over \sin(47\degree)}\text{.}\) 1p ○ Dus \(A\kern{-.8pt}C≈47{,}9\text{.}\) 1p 3p c Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(B\kern{-.8pt}C=25\text{,}\) \(A\kern{-.8pt}C=54\) en \(\angle B=90\degree\text{.}\) Sinus (3) 007i - Sinus, cosinus en tangens - basis - 0ms c Sinus in \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) geeft \(\sin(\angle A)={B\kern{-.8pt}C \over A\kern{-.8pt}C}\) ofwel \(\sin(\angle A)={25 \over 54}\text{.}\) 1p ○ Hieruit volgt \(\angle A=\sin^{-1}({25 \over 54})\text{.}\) 1p ○ Dus \(\angle A≈27{,}6\degree\text{.}\) 1p 3p d Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(A\kern{-.8pt}B=44\text{,}\) \(\angle B=48\degree\) en \(\angle C=90\degree\text{.}\) Cosinus (1) 007j - Sinus, cosinus en tangens - basis - 0ms d Cosinus in \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) geeft \(\cos(\angle B)={B\kern{-.8pt}C \over A\kern{-.8pt}B}\) ofwel \(\cos(48\degree)={B\kern{-.8pt}C \over 44}\text{.}\) 1p ○ Hieruit volgt \(B\kern{-.8pt}C=44⋅\cos(48\degree)\text{.}\) 1p ○ Dus \(B\kern{-.8pt}C≈29{,}4\text{.}\) 1p opgave 23p a Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(A\kern{-.8pt}C=36\text{,}\) \(\angle C=53\degree\) en \(\angle A=90\degree\text{.}\) Cosinus (2) 007k - Sinus, cosinus en tangens - basis - 0ms a Cosinus in \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) geeft \(\cos(\angle C)={A\kern{-.8pt}C \over B\kern{-.8pt}C}\) ofwel \(\cos(53\degree)={36 \over B\kern{-.8pt}C}\text{.}\) 1p ○ Hieruit volgt \(B\kern{-.8pt}C={36 \over \cos(53\degree)}\text{.}\) 1p ○ Dus \(B\kern{-.8pt}C≈59{,}8\text{.}\) 1p 3p b Gegeven is \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) met \(K\kern{-.8pt}L=49\text{,}\) \(K\kern{-.8pt}M=57\) en \(\angle L=90\degree\text{.}\) Cosinus (3) 007l - Sinus, cosinus en tangens - basis - 0ms b Cosinus in \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) geeft \(\cos(\angle K)={K\kern{-.8pt}L \over K\kern{-.8pt}M}\) ofwel \(\cos(\angle K)={49 \over 57}\text{.}\) 1p ○ Hieruit volgt \(\angle K=\cos^{-1}({49 \over 57})\text{.}\) 1p ○ Dus \(\angle K≈30{,}7\degree\text{.}\) 1p |