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 \(K\kern{-.8pt}L=44\text{,}\) \(\angle K=53\degree\) en \(\angle L=90\degree\text{.}\) Tangens (1) 007m - Sinus, cosinus en tangens - basis 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 \(\tan(53\degree)={L\kern{-.8pt}M \over 44}\text{.}\) 1p ○ Hieruit volgt \(L\kern{-.8pt}M=44⋅\tan(53\degree)\text{.}\) 1p ○ Dus \(L\kern{-.8pt}M≈58{,}4\text{.}\) 1p 3p b Gegeven is \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) met \(K\kern{-.8pt}L=56\text{,}\) \(\angle M=40\degree\) en \(\angle K=90\degree\text{.}\) Tangens (2) 007n - Sinus, cosinus en tangens - basis b Tangens in \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) geeft \(\tan(\angle M)={K\kern{-.8pt}L \over K\kern{-.8pt}M}\) ofwel \(\tan(40\degree)={56 \over K\kern{-.8pt}M}\text{.}\) 1p ○ Hieruit volgt \(K\kern{-.8pt}M={56 \over \tan(40\degree)}\text{.}\) 1p ○ Dus \(K\kern{-.8pt}M≈66{,}7\text{.}\) 1p 3p c Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(A\kern{-.8pt}C=40\text{,}\) \(A\kern{-.8pt}B=56\) en \(\angle A=90\degree\text{.}\) Tangens (3) 007o - Sinus, cosinus en tangens - basis 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 \(\tan(\angle C)={56 \over 40}\text{.}\) 1p ○ Hieruit volgt \(\angle C=\tan^{-1}({56 \over 40})\text{.}\) 1p ○ Dus \(\angle C≈54{,}5\degree\text{.}\) 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 \(Q\kern{-.8pt}R=77\text{,}\) \(\angle R=32\degree\) en \(\angle P=90\degree\text{.}\) Sinus (1) 007g - Sinus, cosinus en tangens - basis 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 \(\sin(32\degree)={P\kern{-.8pt}Q \over 77}\text{.}\) 1p ○ Hieruit volgt \(P\kern{-.8pt}Q=77⋅\sin(32\degree)\text{.}\) 1p ○ Dus \(P\kern{-.8pt}Q≈40{,}8\text{.}\) 1p 3p b Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(B\kern{-.8pt}C=60\text{,}\) \(\angle A=54\degree\) en \(\angle B=90\degree\text{.}\) Sinus (2) 007h - Sinus, cosinus en tangens - basis 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 \(\sin(54\degree)={60 \over A\kern{-.8pt}C}\text{.}\) 1p ○ Hieruit volgt \(A\kern{-.8pt}C={60 \over \sin(54\degree)}\text{.}\) 1p ○ Dus \(A\kern{-.8pt}C≈74{,}2\text{.}\) 1p 3p c Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(A\kern{-.8pt}C=32\text{,}\) \(A\kern{-.8pt}B=41\) en \(\angle C=90\degree\text{.}\) Sinus (3) 007i - Sinus, cosinus en tangens - basis c Sinus in \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) geeft \(\sin(\angle B)={A\kern{-.8pt}C \over A\kern{-.8pt}B}\) ofwel \(\sin(\angle B)={32 \over 41}\text{.}\) 1p ○ Hieruit volgt \(\angle B=\sin^{-1}({32 \over 41})\text{.}\) 1p ○ Dus \(\angle B≈51{,}3\degree\text{.}\) 1p 3p d Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(A\kern{-.8pt}B=51\text{,}\) \(\angle B=50\degree\) en \(\angle C=90\degree\text{.}\) Cosinus (1) 007j - Sinus, cosinus en tangens - basis 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 \(\cos(50\degree)={B\kern{-.8pt}C \over 51}\text{.}\) 1p ○ Hieruit volgt \(B\kern{-.8pt}C=51⋅\cos(50\degree)\text{.}\) 1p ○ Dus \(B\kern{-.8pt}C≈32{,}8\text{.}\) 1p opgave 23p a Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(B\kern{-.8pt}C=25\text{,}\) \(\angle B=51\degree\) en \(\angle C=90\degree\text{.}\) Cosinus (2) 007k - Sinus, cosinus en tangens - basis 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 \(\cos(51\degree)={25 \over A\kern{-.8pt}B}\text{.}\) 1p ○ Hieruit volgt \(A\kern{-.8pt}B={25 \over \cos(51\degree)}\text{.}\) 1p ○ Dus \(A\kern{-.8pt}B≈39{,}7\text{.}\) 1p 3p b Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(A\kern{-.8pt}C=43\text{,}\) \(B\kern{-.8pt}C=66\) en \(\angle A=90\degree\text{.}\) Cosinus (3) 007l - Sinus, cosinus en tangens - basis 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 \(\cos(\angle C)={43 \over 66}\text{.}\) 1p ○ Hieruit volgt \(\angle C=\cos^{-1}({43 \over 66})\text{.}\) 1p ○ Dus \(\angle C≈49{,}3\degree\text{.}\) 1p |