Getal & Ruimte (13e editie) - havo wiskunde B
'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 \(L\kern{-.8pt}M=21\text{,}\) \(\angle L=56\degree\) 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 \(\tan(56\degree)={K\kern{-.8pt}M \over 21}\text{.}\) 1p ○ Hieruit volgt \(K\kern{-.8pt}M=21⋅\tan(56\degree)\text{.}\) 1p ○ Dus \(K\kern{-.8pt}M≈31{,}1\text{.}\) 1p 3p b Gegeven is \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) met \(K\kern{-.8pt}M=42\text{,}\) \(\angle L=39\degree\) en \(\angle M=90\degree\text{.}\) Tangens (2) 007n - Sinus, cosinus en tangens - basis - 0ms b Tangens in \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) geeft \(\tan(\angle L)={K\kern{-.8pt}M \over L\kern{-.8pt}M}\) ofwel \(\tan(39\degree)={42 \over L\kern{-.8pt}M}\text{.}\) 1p ○ Hieruit volgt \(L\kern{-.8pt}M={42 \over \tan(39\degree)}\text{.}\) 1p ○ Dus \(L\kern{-.8pt}M≈51{,}9\text{.}\) 1p 3p c Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(P\kern{-.8pt}Q=42\text{,}\) \(Q\kern{-.8pt}R=42\) en \(\angle Q=90\degree\text{.}\) Tangens (3) 007o - Sinus, cosinus en tangens - basis - 0ms c Tangens in \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) geeft \(\tan(\angle P)={Q\kern{-.8pt}R \over P\kern{-.8pt}Q}\) ofwel \(\tan(\angle P)={42 \over 42}\text{.}\) 1p ○ Hieruit volgt \(\angle P=\tan^{-1}({42 \over 42})\text{.}\) 1p ○ Dus \(\angle P=45{,}0\degree\text{.}\) 1p |
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| 3 havo | 6.4 De sinus en de cosinus |
opgave 13p a Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(Q\kern{-.8pt}R=79\text{,}\) \(\angle R=43\degree\) 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 \(\sin(43\degree)={P\kern{-.8pt}Q \over 79}\text{.}\) 1p ○ Hieruit volgt \(P\kern{-.8pt}Q=79⋅\sin(43\degree)\text{.}\) 1p ○ Dus \(P\kern{-.8pt}Q≈53{,}9\text{.}\) 1p 3p b Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(Q\kern{-.8pt}R=36\text{,}\) \(\angle P=39\degree\) 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 \(\sin(39\degree)={36 \over P\kern{-.8pt}R}\text{.}\) 1p ○ Hieruit volgt \(P\kern{-.8pt}R={36 \over \sin(39\degree)}\text{.}\) 1p ○ Dus \(P\kern{-.8pt}R≈57{,}2\text{.}\) 1p 3p c Gegeven is \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) met \(K\kern{-.8pt}L=29\text{,}\) \(L\kern{-.8pt}M=36\) en \(\angle K=90\degree\text{.}\) Sinus (3) 007i - Sinus, cosinus en tangens - basis - 0ms c Sinus in \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) geeft \(\sin(\angle M)={K\kern{-.8pt}L \over L\kern{-.8pt}M}\) ofwel \(\sin(\angle M)={29 \over 36}\text{.}\) 1p ○ Hieruit volgt \(\angle M=\sin^{-1}({29 \over 36})\text{.}\) 1p ○ Dus \(\angle M≈53{,}7\degree\text{.}\) 1p 3p d Gegeven is \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) met \(L\kern{-.8pt}M=52\text{,}\) \(\angle M=47\degree\) en \(\angle K=90\degree\text{.}\) Cosinus (1) 007j - Sinus, cosinus en tangens - basis - 0ms d Cosinus in \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) geeft \(\cos(\angle M)={K\kern{-.8pt}M \over L\kern{-.8pt}M}\) ofwel \(\cos(47\degree)={K\kern{-.8pt}M \over 52}\text{.}\) 1p ○ Hieruit volgt \(K\kern{-.8pt}M=52⋅\cos(47\degree)\text{.}\) 1p ○ Dus \(K\kern{-.8pt}M≈35{,}5\text{.}\) 1p opgave 23p a Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(Q\kern{-.8pt}R=29\text{,}\) \(\angle Q=47\degree\) en \(\angle R=90\degree\text{.}\) Cosinus (2) 007k - Sinus, cosinus en tangens - basis - 0ms a Cosinus in \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) geeft \(\cos(\angle Q)={Q\kern{-.8pt}R \over P\kern{-.8pt}Q}\) ofwel \(\cos(47\degree)={29 \over P\kern{-.8pt}Q}\text{.}\) 1p ○ Hieruit volgt \(P\kern{-.8pt}Q={29 \over \cos(47\degree)}\text{.}\) 1p ○ Dus \(P\kern{-.8pt}Q≈42{,}5\text{.}\) 1p 3p b Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(P\kern{-.8pt}Q=41\text{,}\) \(P\kern{-.8pt}R=57\) en \(\angle Q=90\degree\text{.}\) Cosinus (3) 007l - Sinus, cosinus en tangens - basis - 0ms b Cosinus in \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) geeft \(\cos(\angle P)={P\kern{-.8pt}Q \over P\kern{-.8pt}R}\) ofwel \(\cos(\angle P)={41 \over 57}\text{.}\) 1p ○ Hieruit volgt \(\angle P=\cos^{-1}({41 \over 57})\text{.}\) 1p ○ Dus \(\angle P≈44{,}0\degree\text{.}\) 1p |