Getal & Ruimte (13e editie) - 3 vwo
'Sinus, cosinus en tangens'.
| 3 vwo | 6.3 Berekeningen met de tangens |
opgave 13p a Gegeven is \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) met \(L\kern{-.8pt}M=52\text{,}\) \(\angle L=31\degree\) en \(\angle M=90\degree\text{.}\) Tangens (1) 007m - Sinus, cosinus en tangens - basis - 0ms a Tangens in \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) geeft \(\tan(\angle L)={K\kern{-.8pt}M \over L\kern{-.8pt}M}\) ofwel \(\tan(31\degree)={K\kern{-.8pt}M \over 52}\text{.}\) 1p ○ Hieruit volgt \(K\kern{-.8pt}M=52⋅\tan(31\degree)\text{.}\) 1p ○ Dus \(K\kern{-.8pt}M≈31{,}2\text{.}\) 1p 3p b Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(B\kern{-.8pt}C=46\text{,}\) \(\angle A=32\degree\) 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 \(\tan(32\degree)={46 \over A\kern{-.8pt}B}\text{.}\) 1p ○ Hieruit volgt \(A\kern{-.8pt}B={46 \over \tan(32\degree)}\text{.}\) 1p ○ Dus \(A\kern{-.8pt}B≈73{,}6\text{.}\) 1p 3p c Gegeven is \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) met \(K\kern{-.8pt}L=29\text{,}\) \(L\kern{-.8pt}M=34\) 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 \(\tan(\angle K)={34 \over 29}\text{.}\) 1p ○ Hieruit volgt \(\angle K=\tan^{-1}({34 \over 29})\text{.}\) 1p ○ Dus \(\angle K≈49{,}5\degree\text{.}\) 1p |
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| 3 vwo | 6.4 De sinus en de cosinus |
opgave 13p a Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(Q\kern{-.8pt}R=61\text{,}\) \(\angle R=54\degree\) en \(\angle P=90\degree\text{.}\) Sinus (1) 007g - Sinus, cosinus en tangens - basis - 0ms a Sinus in \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) geeft \(\sin(\angle R)={P\kern{-.8pt}Q \over Q\kern{-.8pt}R}\) ofwel \(\sin(54\degree)={P\kern{-.8pt}Q \over 61}\text{.}\) 1p ○ Hieruit volgt \(P\kern{-.8pt}Q=61⋅\sin(54\degree)\text{.}\) 1p ○ Dus \(P\kern{-.8pt}Q≈49{,}4\text{.}\) 1p 3p b Gegeven is \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) met \(L\kern{-.8pt}M=38\text{,}\) \(\angle K=51\degree\) en \(\angle L=90\degree\text{.}\) Sinus (2) 007h - Sinus, cosinus en tangens - basis - 0ms b Sinus in \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) geeft \(\sin(\angle K)={L\kern{-.8pt}M \over K\kern{-.8pt}M}\) ofwel \(\sin(51\degree)={38 \over K\kern{-.8pt}M}\text{.}\) 1p ○ Hieruit volgt \(K\kern{-.8pt}M={38 \over \sin(51\degree)}\text{.}\) 1p ○ Dus \(K\kern{-.8pt}M≈48{,}9\text{.}\) 1p 3p c Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(B\kern{-.8pt}C=40\text{,}\) \(A\kern{-.8pt}C=67\) 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 \(\sin(\angle A)={40 \over 67}\text{.}\) 1p ○ Hieruit volgt \(\angle A=\sin^{-1}({40 \over 67})\text{.}\) 1p ○ Dus \(\angle A≈36{,}7\degree\text{.}\) 1p 3p d Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(Q\kern{-.8pt}R=77\text{,}\) \(\angle R=54\degree\) en \(\angle P=90\degree\text{.}\) Cosinus (1) 007j - Sinus, cosinus en tangens - basis - 0ms d Cosinus in \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) geeft \(\cos(\angle R)={P\kern{-.8pt}R \over Q\kern{-.8pt}R}\) ofwel \(\cos(54\degree)={P\kern{-.8pt}R \over 77}\text{.}\) 1p ○ Hieruit volgt \(P\kern{-.8pt}R=77⋅\cos(54\degree)\text{.}\) 1p ○ Dus \(P\kern{-.8pt}R≈45{,}3\text{.}\) 1p opgave 23p a Gegeven is \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) met \(K\kern{-.8pt}M=41\text{,}\) \(\angle M=44\degree\) en \(\angle K=90\degree\text{.}\) Cosinus (2) 007k - Sinus, cosinus en tangens - basis - 0ms a Cosinus in \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) geeft \(\cos(\angle M)={K\kern{-.8pt}M \over L\kern{-.8pt}M}\) ofwel \(\cos(44\degree)={41 \over L\kern{-.8pt}M}\text{.}\) 1p ○ Hieruit volgt \(L\kern{-.8pt}M={41 \over \cos(44\degree)}\text{.}\) 1p ○ Dus \(L\kern{-.8pt}M≈57{,}0\text{.}\) 1p 3p b Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(A\kern{-.8pt}B=43\text{,}\) \(A\kern{-.8pt}C=57\) en \(\angle B=90\degree\text{.}\) Cosinus (3) 007l - Sinus, cosinus en tangens - basis - 0ms b Cosinus in \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) geeft \(\cos(\angle A)={A\kern{-.8pt}B \over A\kern{-.8pt}C}\) ofwel \(\cos(\angle A)={43 \over 57}\text{.}\) 1p ○ Hieruit volgt \(\angle A=\cos^{-1}({43 \over 57})\text{.}\) 1p ○ Dus \(\angle A≈41{,}0\degree\text{.}\) 1p |