Getal & Ruimte (13e editie) - havo wiskunde B
'Sinus, cosinus en tangens'.
| 3 havo | 6.3 Berekeningen met de tangens |
opgave 13p a Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(P\kern{-.8pt}Q=60\text{,}\) \(\angle P=31\degree\) 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 \(\tan(31\degree)={Q\kern{-.8pt}R \over 60}\text{.}\) 1p ○ Hieruit volgt \(Q\kern{-.8pt}R=60⋅\tan(31\degree)\text{.}\) 1p ○ Dus \(Q\kern{-.8pt}R≈36{,}1\text{.}\) 1p 3p b Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(P\kern{-.8pt}Q=54\text{,}\) \(\angle R=40\degree\) en \(\angle P=90\degree\text{.}\) Tangens (2) 007n - Sinus, cosinus en tangens - basis - 0ms b Tangens in \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) geeft \(\tan(\angle R)={P\kern{-.8pt}Q \over P\kern{-.8pt}R}\) ofwel \(\tan(40\degree)={54 \over P\kern{-.8pt}R}\text{.}\) 1p ○ Hieruit volgt \(P\kern{-.8pt}R={54 \over \tan(40\degree)}\text{.}\) 1p ○ Dus \(P\kern{-.8pt}R≈64{,}4\text{.}\) 1p 3p c Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(A\kern{-.8pt}C=53\text{,}\) \(A\kern{-.8pt}B=40\) 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 \(\tan(\angle C)={40 \over 53}\text{.}\) 1p ○ Hieruit volgt \(\angle C=\tan^{-1}({40 \over 53})\text{.}\) 1p ○ Dus \(\angle C≈37{,}0\degree\text{.}\) 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 \(L\kern{-.8pt}M=67\text{,}\) \(\angle M=37\degree\) 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 \(\sin(37\degree)={K\kern{-.8pt}L \over 67}\text{.}\) 1p ○ Hieruit volgt \(K\kern{-.8pt}L=67⋅\sin(37\degree)\text{.}\) 1p ○ Dus \(K\kern{-.8pt}L≈40{,}3\text{.}\) 1p 3p b Gegeven is \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) met \(K\kern{-.8pt}L=49\text{,}\) \(\angle M=50\degree\) en \(\angle K=90\degree\text{.}\) Sinus (2) 007h - Sinus, cosinus en tangens - basis - 0ms b Sinus in \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) geeft \(\sin(\angle M)={K\kern{-.8pt}L \over L\kern{-.8pt}M}\) ofwel \(\sin(50\degree)={49 \over L\kern{-.8pt}M}\text{.}\) 1p ○ Hieruit volgt \(L\kern{-.8pt}M={49 \over \sin(50\degree)}\text{.}\) 1p ○ Dus \(L\kern{-.8pt}M≈64{,}0\text{.}\) 1p 3p c Gegeven is \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) met \(K\kern{-.8pt}L=48\text{,}\) \(L\kern{-.8pt}M=61\) 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 \(\sin(\angle M)={48 \over 61}\text{.}\) 1p ○ Hieruit volgt \(\angle M=\sin^{-1}({48 \over 61})\text{.}\) 1p ○ Dus \(\angle M≈51{,}9\degree\text{.}\) 1p 3p d Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(P\kern{-.8pt}R=58\text{,}\) \(\angle P=52\degree\) en \(\angle Q=90\degree\text{.}\) Cosinus (1) 007j - Sinus, cosinus en tangens - basis - 0ms d Cosinus in \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) geeft \(\cos(\angle P)={P\kern{-.8pt}Q \over P\kern{-.8pt}R}\) ofwel \(\cos(52\degree)={P\kern{-.8pt}Q \over 58}\text{.}\) 1p ○ Hieruit volgt \(P\kern{-.8pt}Q=58⋅\cos(52\degree)\text{.}\) 1p ○ Dus \(P\kern{-.8pt}Q≈35{,}7\text{.}\) 1p opgave 23p a Gegeven is \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) met \(K\kern{-.8pt}M=52\text{,}\) \(\angle M=44\degree\) 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 \(\cos(44\degree)={52 \over L\kern{-.8pt}M}\text{.}\) 1p ○ Hieruit volgt \(L\kern{-.8pt}M={52 \over \cos(44\degree)}\text{.}\) 1p ○ Dus \(L\kern{-.8pt}M≈72{,}3\text{.}\) 1p 3p b Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(Q\kern{-.8pt}R=50\text{,}\) \(P\kern{-.8pt}Q=56\) en \(\angle R=90\degree\text{.}\) Cosinus (3) 007l - Sinus, cosinus en tangens - basis - 1ms b Cosinus in \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) geeft \(\cos(\angle Q)={Q\kern{-.8pt}R \over P\kern{-.8pt}Q}\) ofwel \(\cos(\angle Q)={50 \over 56}\text{.}\) 1p ○ Hieruit volgt \(\angle Q=\cos^{-1}({50 \over 56})\text{.}\) 1p ○ Dus \(\angle Q≈26{,}8\degree\text{.}\) 1p |