Getal & Ruimte (13e editie) - 3 havo
'Sinus, cosinus en tangens'.
| 3 havo | 6.3 Berekeningen met de tangens |
opgave 13p a Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(A\kern{-.8pt}B=36\text{,}\) \(\angle A=38\degree\) en \(\angle B=90\degree\text{.}\) Tangens (1) 007m - Sinus, cosinus en tangens - basis - 0ms a Tangens in \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) geeft \(\tan(\angle A)={B\kern{-.8pt}C \over A\kern{-.8pt}B}\) ofwel \(\tan(38\degree)={B\kern{-.8pt}C \over 36}\text{.}\) 1p ○ Hieruit volgt \(B\kern{-.8pt}C=36⋅\tan(38\degree)\text{.}\) 1p ○ Dus \(B\kern{-.8pt}C≈28{,}1\text{.}\) 1p 3p b Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(P\kern{-.8pt}R=27\text{,}\) \(\angle Q=46\degree\) en \(\angle R=90\degree\text{.}\) Tangens (2) 007n - Sinus, cosinus en tangens - basis - 0ms b Tangens in \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) geeft \(\tan(\angle Q)={P\kern{-.8pt}R \over Q\kern{-.8pt}R}\) ofwel \(\tan(46\degree)={27 \over Q\kern{-.8pt}R}\text{.}\) 1p ○ Hieruit volgt \(Q\kern{-.8pt}R={27 \over \tan(46\degree)}\text{.}\) 1p ○ Dus \(Q\kern{-.8pt}R≈26{,}1\text{.}\) 1p 3p c Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(A\kern{-.8pt}C=44\text{,}\) \(A\kern{-.8pt}B=55\) 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 \(\tan(\angle C)={55 \over 44}\text{.}\) 1p ○ Hieruit volgt \(\angle C=\tan^{-1}({55 \over 44})\text{.}\) 1p ○ Dus \(\angle C≈51{,}3\degree\text{.}\) 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 \(Q\kern{-.8pt}R=40\text{,}\) \(\angle R=47\degree\) 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 \(\sin(47\degree)={P\kern{-.8pt}Q \over 40}\text{.}\) 1p ○ Hieruit volgt \(P\kern{-.8pt}Q=40⋅\sin(47\degree)\text{.}\) 1p ○ Dus \(P\kern{-.8pt}Q≈29{,}3\text{.}\) 1p 3p b Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(Q\kern{-.8pt}R=47\text{,}\) \(\angle P=59\degree\) 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 \(\sin(59\degree)={47 \over P\kern{-.8pt}R}\text{.}\) 1p ○ Hieruit volgt \(P\kern{-.8pt}R={47 \over \sin(59\degree)}\text{.}\) 1p ○ Dus \(P\kern{-.8pt}R≈54{,}8\text{.}\) 1p 3p c Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(A\kern{-.8pt}C=21\text{,}\) \(A\kern{-.8pt}B=57\) en \(\angle C=90\degree\text{.}\) Sinus (3) 007i - Sinus, cosinus en tangens - basis - 0ms c Sinus in \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) geeft \(\sin(\angle B)={A\kern{-.8pt}C \over A\kern{-.8pt}B}\) ofwel \(\sin(\angle B)={21 \over 57}\text{.}\) 1p ○ Hieruit volgt \(\angle B=\sin^{-1}({21 \over 57})\text{.}\) 1p ○ Dus \(\angle B≈21{,}6\degree\text{.}\) 1p 3p d Gegeven is \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) met \(K\kern{-.8pt}L=57\text{,}\) \(\angle L=48\degree\) 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 \(\cos(48\degree)={L\kern{-.8pt}M \over 57}\text{.}\) 1p ○ Hieruit volgt \(L\kern{-.8pt}M=57⋅\cos(48\degree)\text{.}\) 1p ○ Dus \(L\kern{-.8pt}M≈38{,}1\text{.}\) 1p opgave 23p a Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(A\kern{-.8pt}B=43\text{,}\) \(\angle A=59\degree\) en \(\angle B=90\degree\text{.}\) Cosinus (2) 007k - Sinus, cosinus en tangens - basis - 0ms a Cosinus in \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) geeft \(\cos(\angle A)={A\kern{-.8pt}B \over A\kern{-.8pt}C}\) ofwel \(\cos(59\degree)={43 \over A\kern{-.8pt}C}\text{.}\) 1p ○ Hieruit volgt \(A\kern{-.8pt}C={43 \over \cos(59\degree)}\text{.}\) 1p ○ Dus \(A\kern{-.8pt}C≈83{,}5\text{.}\) 1p 3p b Gegeven is \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) met \(K\kern{-.8pt}M=44\text{,}\) \(L\kern{-.8pt}M=74\) en \(\angle K=90\degree\text{.}\) Cosinus (3) 007l - Sinus, cosinus en tangens - basis - 0ms b Cosinus in \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) geeft \(\cos(\angle M)={K\kern{-.8pt}M \over L\kern{-.8pt}M}\) ofwel \(\cos(\angle M)={44 \over 74}\text{.}\) 1p ○ Hieruit volgt \(\angle M=\cos^{-1}({44 \over 74})\text{.}\) 1p ○ Dus \(\angle M≈53{,}5\degree\text{.}\) 1p |