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 \(K\kern{-.8pt}L=41\text{,}\) \(\angle K=50\degree\) 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 \(\tan(50\degree)={L\kern{-.8pt}M \over 41}\text{.}\) 1p ○ Hieruit volgt \(L\kern{-.8pt}M=41⋅\tan(50\degree)\text{.}\) 1p ○ Dus \(L\kern{-.8pt}M≈48{,}9\text{.}\) 1p 3p b Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(A\kern{-.8pt}B=40\text{,}\) \(\angle C=59\degree\) en \(\angle A=90\degree\text{.}\) Tangens (2) 007n - Sinus, cosinus en tangens - basis - 0ms b Tangens in \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) geeft \(\tan(\angle C)={A\kern{-.8pt}B \over A\kern{-.8pt}C}\) ofwel \(\tan(59\degree)={40 \over A\kern{-.8pt}C}\text{.}\) 1p ○ Hieruit volgt \(A\kern{-.8pt}C={40 \over \tan(59\degree)}\text{.}\) 1p ○ Dus \(A\kern{-.8pt}C≈24{,}0\text{.}\) 1p 3p c Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(A\kern{-.8pt}C=49\text{,}\) \(A\kern{-.8pt}B=43\) 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 \(\tan(\angle C)={43 \over 49}\text{.}\) 1p ○ Hieruit volgt \(\angle C=\tan^{-1}({43 \over 49})\text{.}\) 1p ○ Dus \(\angle C≈41{,}3\degree\text{.}\) 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 \(P\kern{-.8pt}Q=63\text{,}\) \(\angle Q=47\degree\) en \(\angle R=90\degree\text{.}\) Sinus (1) 007g - Sinus, cosinus en tangens - basis - 0ms a Sinus in \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) geeft \(\sin(\angle Q)={P\kern{-.8pt}R \over P\kern{-.8pt}Q}\) ofwel \(\sin(47\degree)={P\kern{-.8pt}R \over 63}\text{.}\) 1p ○ Hieruit volgt \(P\kern{-.8pt}R=63⋅\sin(47\degree)\text{.}\) 1p ○ Dus \(P\kern{-.8pt}R≈46{,}1\text{.}\) 1p 3p b Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(Q\kern{-.8pt}R=50\text{,}\) \(\angle P=54\degree\) en \(\angle Q=90\degree\text{.}\) Sinus (2) 007h - Sinus, cosinus en tangens - basis - 0ms b Sinus in \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) geeft \(\sin(\angle P)={Q\kern{-.8pt}R \over P\kern{-.8pt}R}\) ofwel \(\sin(54\degree)={50 \over P\kern{-.8pt}R}\text{.}\) 1p ○ Hieruit volgt \(P\kern{-.8pt}R={50 \over \sin(54\degree)}\text{.}\) 1p ○ Dus \(P\kern{-.8pt}R≈61{,}8\text{.}\) 1p 3p c Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(B\kern{-.8pt}C=22\text{,}\) \(A\kern{-.8pt}C=40\) 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 \(\sin(\angle A)={22 \over 40}\text{.}\) 1p ○ Hieruit volgt \(\angle A=\sin^{-1}({22 \over 40})\text{.}\) 1p ○ Dus \(\angle A≈33{,}4\degree\text{.}\) 1p 3p d Gegeven is \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) met \(K\kern{-.8pt}L=40\text{,}\) \(\angle L=53\degree\) en \(\angle M=90\degree\text{.}\) Cosinus (1) 007j - Sinus, cosinus en tangens - basis - 0ms d Cosinus in \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) geeft \(\cos(\angle L)={L\kern{-.8pt}M \over K\kern{-.8pt}L}\) ofwel \(\cos(53\degree)={L\kern{-.8pt}M \over 40}\text{.}\) 1p ○ Hieruit volgt \(L\kern{-.8pt}M=40⋅\cos(53\degree)\text{.}\) 1p ○ Dus \(L\kern{-.8pt}M≈24{,}1\text{.}\) 1p opgave 23p a Gegeven is \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) met \(K\kern{-.8pt}M=50\text{,}\) \(\angle M=36\degree\) 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 \(\cos(36\degree)={50 \over L\kern{-.8pt}M}\text{.}\) 1p ○ Hieruit volgt \(L\kern{-.8pt}M={50 \over \cos(36\degree)}\text{.}\) 1p ○ Dus \(L\kern{-.8pt}M≈61{,}8\text{.}\) 1p 3p b Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(P\kern{-.8pt}R=36\text{,}\) \(Q\kern{-.8pt}R=52\) en \(\angle P=90\degree\text{.}\) Cosinus (3) 007l - Sinus, cosinus en tangens - basis - 0ms b Cosinus in \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) geeft \(\cos(\angle R)={P\kern{-.8pt}R \over Q\kern{-.8pt}R}\) ofwel \(\cos(\angle R)={36 \over 52}\text{.}\) 1p ○ Hieruit volgt \(\angle R=\cos^{-1}({36 \over 52})\text{.}\) 1p ○ Dus \(\angle R≈46{,}2\degree\text{.}\) 1p |