Getal & Ruimte (13e editie) - 3 havo
'Sinus, cosinus en tangens'.
| 3 havo | 6.3 Berekeningen met de tangens |
opgave 13p a Gegeven is \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) met \(K\kern{-.8pt}M=59\text{,}\) \(\angle M=31\degree\) en \(\angle K=90\degree\text{.}\) Tangens (1) 007m - Sinus, cosinus en tangens - basis - 0ms a Tangens in \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) geeft \(\tan(\angle M)={K\kern{-.8pt}L \over K\kern{-.8pt}M}\) ofwel \(\tan(31\degree)={K\kern{-.8pt}L \over 59}\text{.}\) 1p ○ Hieruit volgt \(K\kern{-.8pt}L=59⋅\tan(31\degree)\text{.}\) 1p ○ Dus \(K\kern{-.8pt}L≈35{,}5\text{.}\) 1p 3p b Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(B\kern{-.8pt}C=53\text{,}\) \(\angle A=34\degree\) en \(\angle B=90\degree\text{.}\) Tangens (2) 007n - Sinus, cosinus en tangens - basis - 0ms b Tangens in \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) geeft \(\tan(\angle A)={B\kern{-.8pt}C \over A\kern{-.8pt}B}\) ofwel \(\tan(34\degree)={53 \over A\kern{-.8pt}B}\text{.}\) 1p ○ Hieruit volgt \(A\kern{-.8pt}B={53 \over \tan(34\degree)}\text{.}\) 1p ○ Dus \(A\kern{-.8pt}B≈78{,}6\text{.}\) 1p 3p c Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(Q\kern{-.8pt}R=45\text{,}\) \(P\kern{-.8pt}R=38\) en \(\angle R=90\degree\text{.}\) Tangens (3) 007o - Sinus, cosinus en tangens - basis - 0ms c Tangens in \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) geeft \(\tan(\angle Q)={P\kern{-.8pt}R \over Q\kern{-.8pt}R}\) ofwel \(\tan(\angle Q)={38 \over 45}\text{.}\) 1p ○ Hieruit volgt \(\angle Q=\tan^{-1}({38 \over 45})\text{.}\) 1p ○ Dus \(\angle Q≈40{,}2\degree\text{.}\) 1p |
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| 3 havo | 6.4 De sinus en de cosinus |
opgave 13p a Gegeven is \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) met \(K\kern{-.8pt}M=78\text{,}\) \(\angle K=36\degree\) en \(\angle L=90\degree\text{.}\) Sinus (1) 007g - Sinus, cosinus en tangens - basis - 0ms a Sinus in \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) geeft \(\sin(\angle K)={L\kern{-.8pt}M \over K\kern{-.8pt}M}\) ofwel \(\sin(36\degree)={L\kern{-.8pt}M \over 78}\text{.}\) 1p ○ Hieruit volgt \(L\kern{-.8pt}M=78⋅\sin(36\degree)\text{.}\) 1p ○ Dus \(L\kern{-.8pt}M≈45{,}8\text{.}\) 1p 3p b Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(A\kern{-.8pt}B=35\text{,}\) \(\angle C=58\degree\) 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 \(\sin(58\degree)={35 \over B\kern{-.8pt}C}\text{.}\) 1p ○ Hieruit volgt \(B\kern{-.8pt}C={35 \over \sin(58\degree)}\text{.}\) 1p ○ Dus \(B\kern{-.8pt}C≈41{,}3\text{.}\) 1p 3p c Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(A\kern{-.8pt}B=43\text{,}\) \(B\kern{-.8pt}C=50\) en \(\angle A=90\degree\text{.}\) Sinus (3) 007i - Sinus, cosinus en tangens - basis - 0ms c Sinus in \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) geeft \(\sin(\angle C)={A\kern{-.8pt}B \over B\kern{-.8pt}C}\) ofwel \(\sin(\angle C)={43 \over 50}\text{.}\) 1p ○ Hieruit volgt \(\angle C=\sin^{-1}({43 \over 50})\text{.}\) 1p ○ Dus \(\angle C≈59{,}3\degree\text{.}\) 1p 3p d Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(P\kern{-.8pt}R=67\text{,}\) \(\angle P=53\degree\) en \(\angle Q=90\degree\text{.}\) Cosinus (1) 007j - Sinus, cosinus en tangens - basis - 0ms d Cosinus in \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) geeft \(\cos(\angle P)={P\kern{-.8pt}Q \over P\kern{-.8pt}R}\) ofwel \(\cos(53\degree)={P\kern{-.8pt}Q \over 67}\text{.}\) 1p ○ Hieruit volgt \(P\kern{-.8pt}Q=67⋅\cos(53\degree)\text{.}\) 1p ○ Dus \(P\kern{-.8pt}Q≈40{,}3\text{.}\) 1p opgave 23p a Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(A\kern{-.8pt}C=29\text{,}\) \(\angle C=40\degree\) 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 \(\cos(40\degree)={29 \over B\kern{-.8pt}C}\text{.}\) 1p ○ Hieruit volgt \(B\kern{-.8pt}C={29 \over \cos(40\degree)}\text{.}\) 1p ○ Dus \(B\kern{-.8pt}C≈37{,}9\text{.}\) 1p 3p b Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(A\kern{-.8pt}C=45\text{,}\) \(B\kern{-.8pt}C=50\) en \(\angle A=90\degree\text{.}\) Cosinus (3) 007l - Sinus, cosinus en tangens - basis - 0ms b Cosinus in \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) geeft \(\cos(\angle C)={A\kern{-.8pt}C \over B\kern{-.8pt}C}\) ofwel \(\cos(\angle C)={45 \over 50}\text{.}\) 1p ○ Hieruit volgt \(\angle C=\cos^{-1}({45 \over 50})\text{.}\) 1p ○ Dus \(\angle C≈25{,}8\degree\text{.}\) 1p |