Getal & Ruimte (13e editie) - 3 havo
'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 \(P\kern{-.8pt}Q=22\text{,}\) \(\angle P=46\degree\) 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 \(\tan(46\degree)={Q\kern{-.8pt}R \over 22}\text{.}\) 1p ○ Hieruit volgt \(Q\kern{-.8pt}R=22⋅\tan(46\degree)\text{.}\) 1p ○ Dus \(Q\kern{-.8pt}R≈22{,}8\text{.}\) 1p 3p b Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(B\kern{-.8pt}C=56\text{,}\) \(\angle A=53\degree\) 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 \(\tan(53\degree)={56 \over A\kern{-.8pt}B}\text{.}\) 1p ○ Hieruit volgt \(A\kern{-.8pt}B={56 \over \tan(53\degree)}\text{.}\) 1p ○ Dus \(A\kern{-.8pt}B≈42{,}2\text{.}\) 1p 3p c Gegeven is \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) met \(L\kern{-.8pt}M=60\text{,}\) \(K\kern{-.8pt}M=38\) en \(\angle M=90\degree\text{.}\) Tangens (3) 007o - Sinus, cosinus en tangens - basis - 0ms c Tangens in \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) geeft \(\tan(\angle L)={K\kern{-.8pt}M \over L\kern{-.8pt}M}\) ofwel \(\tan(\angle L)={38 \over 60}\text{.}\) 1p ○ Hieruit volgt \(\angle L=\tan^{-1}({38 \over 60})\text{.}\) 1p ○ Dus \(\angle L≈32{,}3\degree\text{.}\) 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 \(L\kern{-.8pt}M=80\text{,}\) \(\angle M=56\degree\) en \(\angle K=90\degree\text{.}\) Sinus (1) 007g - Sinus, cosinus en tangens - basis - 0ms a Sinus in \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) geeft \(\sin(\angle M)={K\kern{-.8pt}L \over L\kern{-.8pt}M}\) ofwel \(\sin(56\degree)={K\kern{-.8pt}L \over 80}\text{.}\) 1p ○ Hieruit volgt \(K\kern{-.8pt}L=80⋅\sin(56\degree)\text{.}\) 1p ○ Dus \(K\kern{-.8pt}L≈66{,}3\text{.}\) 1p 3p b Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(B\kern{-.8pt}C=22\text{,}\) \(\angle A=48\degree\) 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 \(\sin(48\degree)={22 \over A\kern{-.8pt}C}\text{.}\) 1p ○ Hieruit volgt \(A\kern{-.8pt}C={22 \over \sin(48\degree)}\text{.}\) 1p ○ Dus \(A\kern{-.8pt}C≈29{,}6\text{.}\) 1p 3p c Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(P\kern{-.8pt}R=26\text{,}\) \(P\kern{-.8pt}Q=35\) en \(\angle R=90\degree\text{.}\) Sinus (3) 007i - Sinus, cosinus en tangens - basis - 0ms c Sinus in \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) geeft \(\sin(\angle Q)={P\kern{-.8pt}R \over P\kern{-.8pt}Q}\) ofwel \(\sin(\angle Q)={26 \over 35}\text{.}\) 1p ○ Hieruit volgt \(\angle Q=\sin^{-1}({26 \over 35})\text{.}\) 1p ○ Dus \(\angle Q≈48{,}0\degree\text{.}\) 1p 3p d Gegeven is \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) met \(K\kern{-.8pt}M=43\text{,}\) \(\angle K=50\degree\) 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 \(\cos(50\degree)={K\kern{-.8pt}L \over 43}\text{.}\) 1p ○ Hieruit volgt \(K\kern{-.8pt}L=43⋅\cos(50\degree)\text{.}\) 1p ○ Dus \(K\kern{-.8pt}L≈27{,}6\text{.}\) 1p opgave 23p a Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(B\kern{-.8pt}C=47\text{,}\) \(\angle B=43\degree\) en \(\angle C=90\degree\text{.}\) Cosinus (2) 007k - Sinus, cosinus en tangens - basis - 0ms a Cosinus in \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) geeft \(\cos(\angle B)={B\kern{-.8pt}C \over A\kern{-.8pt}B}\) ofwel \(\cos(43\degree)={47 \over A\kern{-.8pt}B}\text{.}\) 1p ○ Hieruit volgt \(A\kern{-.8pt}B={47 \over \cos(43\degree)}\text{.}\) 1p ○ Dus \(A\kern{-.8pt}B≈64{,}3\text{.}\) 1p 3p b Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(A\kern{-.8pt}C=30\text{,}\) \(B\kern{-.8pt}C=43\) 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 \(\cos(\angle C)={30 \over 43}\text{.}\) 1p ○ Hieruit volgt \(\angle C=\cos^{-1}({30 \over 43})\text{.}\) 1p ○ Dus \(\angle C≈45{,}8\degree\text{.}\) 1p |