Getal & Ruimte (13e editie) - vwo wiskunde B
'Sinus, cosinus en tangens'.
| 3 vwo | 6.3 Berekeningen met de tangens |
opgave 13p a Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(B\kern{-.8pt}C=47\text{,}\) \(\angle B=55\degree\) en \(\angle C=90\degree\text{.}\) Tangens (1) 007m - Sinus, cosinus en tangens - basis - 0ms a Tangens in \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) geeft \(\tan(\angle B)={A\kern{-.8pt}C \over B\kern{-.8pt}C}\) ofwel \(\tan(55\degree)={A\kern{-.8pt}C \over 47}\text{.}\) 1p ○ Hieruit volgt \(A\kern{-.8pt}C=47⋅\tan(55\degree)\text{.}\) 1p ○ Dus \(A\kern{-.8pt}C≈67{,}1\text{.}\) 1p 3p b Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(A\kern{-.8pt}C=49\text{,}\) \(\angle B=32\degree\) en \(\angle C=90\degree\text{.}\) Tangens (2) 007n - Sinus, cosinus en tangens - basis - 0ms b Tangens in \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) geeft \(\tan(\angle B)={A\kern{-.8pt}C \over B\kern{-.8pt}C}\) ofwel \(\tan(32\degree)={49 \over B\kern{-.8pt}C}\text{.}\) 1p ○ Hieruit volgt \(B\kern{-.8pt}C={49 \over \tan(32\degree)}\text{.}\) 1p ○ Dus \(B\kern{-.8pt}C≈78{,}4\text{.}\) 1p 3p c Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(B\kern{-.8pt}C=22\text{,}\) \(A\kern{-.8pt}C=33\) en \(\angle C=90\degree\text{.}\) Tangens (3) 007o - Sinus, cosinus en tangens - basis - 0ms c Tangens in \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) geeft \(\tan(\angle B)={A\kern{-.8pt}C \over B\kern{-.8pt}C}\) ofwel \(\tan(\angle B)={33 \over 22}\text{.}\) 1p ○ Hieruit volgt \(\angle B=\tan^{-1}({33 \over 22})\text{.}\) 1p ○ Dus \(\angle B≈56{,}3\degree\text{.}\) 1p |
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| 3 vwo | 6.4 De sinus en de cosinus |
opgave 13p a Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(A\kern{-.8pt}C=47\text{,}\) \(\angle A=51\degree\) en \(\angle B=90\degree\text{.}\) Sinus (1) 007g - Sinus, cosinus en tangens - basis - 0ms a Sinus in \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) geeft \(\sin(\angle A)={B\kern{-.8pt}C \over A\kern{-.8pt}C}\) ofwel \(\sin(51\degree)={B\kern{-.8pt}C \over 47}\text{.}\) 1p ○ Hieruit volgt \(B\kern{-.8pt}C=47⋅\sin(51\degree)\text{.}\) 1p ○ Dus \(B\kern{-.8pt}C≈36{,}5\text{.}\) 1p 3p b Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(A\kern{-.8pt}B=40\text{,}\) \(\angle C=53\degree\) en \(\angle A=90\degree\text{.}\) Sinus (2) 007h - Sinus, cosinus en tangens - basis - 0ms b Sinus in \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) geeft \(\sin(\angle C)={A\kern{-.8pt}B \over B\kern{-.8pt}C}\) ofwel \(\sin(53\degree)={40 \over B\kern{-.8pt}C}\text{.}\) 1p ○ Hieruit volgt \(B\kern{-.8pt}C={40 \over \sin(53\degree)}\text{.}\) 1p ○ Dus \(B\kern{-.8pt}C≈50{,}1\text{.}\) 1p 3p c Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(Q\kern{-.8pt}R=48\text{,}\) \(P\kern{-.8pt}R=76\) en \(\angle Q=90\degree\text{.}\) Sinus (3) 007i - Sinus, cosinus en tangens - basis - 0ms c Sinus in \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) geeft \(\sin(\angle P)={Q\kern{-.8pt}R \over P\kern{-.8pt}R}\) ofwel \(\sin(\angle P)={48 \over 76}\text{.}\) 1p ○ Hieruit volgt \(\angle P=\sin^{-1}({48 \over 76})\text{.}\) 1p ○ Dus \(\angle P≈39{,}2\degree\text{.}\) 1p 3p d Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(A\kern{-.8pt}C=55\text{,}\) \(\angle A=33\degree\) en \(\angle B=90\degree\text{.}\) Cosinus (1) 007j - Sinus, cosinus en tangens - basis - 0ms d Cosinus in \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) geeft \(\cos(\angle A)={A\kern{-.8pt}B \over A\kern{-.8pt}C}\) ofwel \(\cos(33\degree)={A\kern{-.8pt}B \over 55}\text{.}\) 1p ○ Hieruit volgt \(A\kern{-.8pt}B=55⋅\cos(33\degree)\text{.}\) 1p ○ Dus \(A\kern{-.8pt}B≈46{,}1\text{.}\) 1p opgave 23p a Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(A\kern{-.8pt}B=31\text{,}\) \(\angle A=58\degree\) 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 \(\cos(58\degree)={31 \over A\kern{-.8pt}C}\text{.}\) 1p ○ Hieruit volgt \(A\kern{-.8pt}C={31 \over \cos(58\degree)}\text{.}\) 1p ○ Dus \(A\kern{-.8pt}C≈58{,}5\text{.}\) 1p 3p b Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(Q\kern{-.8pt}R=20\text{,}\) \(P\kern{-.8pt}Q=33\) en \(\angle R=90\degree\text{.}\) Cosinus (3) 007l - Sinus, cosinus en tangens - basis - 0ms b Cosinus in \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) geeft \(\cos(\angle Q)={Q\kern{-.8pt}R \over P\kern{-.8pt}Q}\) ofwel \(\cos(\angle Q)={20 \over 33}\text{.}\) 1p ○ Hieruit volgt \(\angle Q=\cos^{-1}({20 \over 33})\text{.}\) 1p ○ Dus \(\angle Q≈52{,}7\degree\text{.}\) 1p |