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 \(K\kern{-.8pt}L=29\text{,}\) \(\angle K=56\degree\) en \(\angle L=90\degree\text{.}\) Tangens (1) 007m - Sinus, cosinus en tangens - basis - 0ms a Tangens in \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) geeft \(\tan(\angle K)={L\kern{-.8pt}M \over K\kern{-.8pt}L}\) ofwel \(\tan(56\degree)={L\kern{-.8pt}M \over 29}\text{.}\) 1p ○ Hieruit volgt \(L\kern{-.8pt}M=29⋅\tan(56\degree)\text{.}\) 1p ○ Dus \(L\kern{-.8pt}M≈43{,}0\text{.}\) 1p 3p b Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(B\kern{-.8pt}C=34\text{,}\) \(\angle A=56\degree\) 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 \(\tan(56\degree)={34 \over A\kern{-.8pt}B}\text{.}\) 1p ○ Hieruit volgt \(A\kern{-.8pt}B={34 \over \tan(56\degree)}\text{.}\) 1p ○ Dus \(A\kern{-.8pt}B≈22{,}9\text{.}\) 1p 3p c Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(A\kern{-.8pt}C=47\text{,}\) \(A\kern{-.8pt}B=51\) 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 \(\tan(\angle C)={51 \over 47}\text{.}\) 1p ○ Hieruit volgt \(\angle C=\tan^{-1}({51 \over 47})\text{.}\) 1p ○ Dus \(\angle C≈47{,}3\degree\text{.}\) 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 \(A\kern{-.8pt}B=68\text{,}\) \(\angle B=34\degree\) 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 \(\sin(34\degree)={A\kern{-.8pt}C \over 68}\text{.}\) 1p ○ Hieruit volgt \(A\kern{-.8pt}C=68⋅\sin(34\degree)\text{.}\) 1p ○ Dus \(A\kern{-.8pt}C≈38{,}0\text{.}\) 1p 3p b Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(P\kern{-.8pt}R=55\text{,}\) \(\angle Q=50\degree\) 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 \(\sin(50\degree)={55 \over P\kern{-.8pt}Q}\text{.}\) 1p ○ Hieruit volgt \(P\kern{-.8pt}Q={55 \over \sin(50\degree)}\text{.}\) 1p ○ Dus \(P\kern{-.8pt}Q≈71{,}8\text{.}\) 1p 3p c Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(Q\kern{-.8pt}R=38\text{,}\) \(P\kern{-.8pt}R=60\) en \(\angle Q=90\degree\text{.}\) Sinus (3) 007i - Sinus, cosinus en tangens - basis - 0ms c Sinus in \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) geeft \(\sin(\angle P)={Q\kern{-.8pt}R \over P\kern{-.8pt}R}\) ofwel \(\sin(\angle P)={38 \over 60}\text{.}\) 1p ○ Hieruit volgt \(\angle P=\sin^{-1}({38 \over 60})\text{.}\) 1p ○ Dus \(\angle P≈39{,}3\degree\text{.}\) 1p 3p d Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(B\kern{-.8pt}C=44\text{,}\) \(\angle C=34\degree\) 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 \(\cos(34\degree)={A\kern{-.8pt}C \over 44}\text{.}\) 1p ○ Hieruit volgt \(A\kern{-.8pt}C=44⋅\cos(34\degree)\text{.}\) 1p ○ Dus \(A\kern{-.8pt}C≈36{,}5\text{.}\) 1p opgave 23p a Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(A\kern{-.8pt}C=28\text{,}\) \(\angle C=35\degree\) 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 \(\cos(35\degree)={28 \over B\kern{-.8pt}C}\text{.}\) 1p ○ Hieruit volgt \(B\kern{-.8pt}C={28 \over \cos(35\degree)}\text{.}\) 1p ○ Dus \(B\kern{-.8pt}C≈34{,}2\text{.}\) 1p 3p b Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(A\kern{-.8pt}C=59\text{,}\) \(B\kern{-.8pt}C=72\) 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 \(\cos(\angle C)={59 \over 72}\text{.}\) 1p ○ Hieruit volgt \(\angle C=\cos^{-1}({59 \over 72})\text{.}\) 1p ○ Dus \(\angle C≈35{,}0\degree\text{.}\) 1p |