Getal & Ruimte (13e editie) - 3 vwo
'Sinus, cosinus en tangens'.
| 3 vwo | 6.3 Berekeningen met de tangens |
opgave 13p a Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(Q\kern{-.8pt}R=49\text{,}\) \(\angle Q=35\degree\) en \(\angle R=90\degree\text{.}\) Tangens (1) 007m - Sinus, cosinus en tangens - basis - 0ms a Tangens in \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) geeft \(\tan(\angle Q)={P\kern{-.8pt}R \over Q\kern{-.8pt}R}\) ofwel \(\tan(35\degree)={P\kern{-.8pt}R \over 49}\text{.}\) 1p ○ Hieruit volgt \(P\kern{-.8pt}R=49⋅\tan(35\degree)\text{.}\) 1p ○ Dus \(P\kern{-.8pt}R≈34{,}3\text{.}\) 1p 3p b Gegeven is \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) met \(K\kern{-.8pt}M=21\text{,}\) \(\angle L=58\degree\) 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 \(\tan(58\degree)={21 \over L\kern{-.8pt}M}\text{.}\) 1p ○ Hieruit volgt \(L\kern{-.8pt}M={21 \over \tan(58\degree)}\text{.}\) 1p ○ Dus \(L\kern{-.8pt}M≈13{,}1\text{.}\) 1p 3p c Gegeven is \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) met \(L\kern{-.8pt}M=53\text{,}\) \(K\kern{-.8pt}M=51\) en \(\angle M=90\degree\text{.}\) Tangens (3) 007o - Sinus, cosinus en tangens - basis - 0ms c Tangens in \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) geeft \(\tan(\angle L)={K\kern{-.8pt}M \over L\kern{-.8pt}M}\) ofwel \(\tan(\angle L)={51 \over 53}\text{.}\) 1p ○ Hieruit volgt \(\angle L=\tan^{-1}({51 \over 53})\text{.}\) 1p ○ Dus \(\angle L≈43{,}9\degree\text{.}\) 1p |
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| 3 vwo | 6.4 De sinus en de cosinus |
opgave 13p a Gegeven is \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) met \(L\kern{-.8pt}M=54\text{,}\) \(\angle M=38\degree\) 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 \(\sin(38\degree)={K\kern{-.8pt}L \over 54}\text{.}\) 1p ○ Hieruit volgt \(K\kern{-.8pt}L=54⋅\sin(38\degree)\text{.}\) 1p ○ Dus \(K\kern{-.8pt}L≈33{,}2\text{.}\) 1p 3p b Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(A\kern{-.8pt}B=33\text{,}\) \(\angle C=44\degree\) 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 \(\sin(44\degree)={33 \over B\kern{-.8pt}C}\text{.}\) 1p ○ Hieruit volgt \(B\kern{-.8pt}C={33 \over \sin(44\degree)}\text{.}\) 1p ○ Dus \(B\kern{-.8pt}C≈47{,}5\text{.}\) 1p 3p c Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(Q\kern{-.8pt}R=58\text{,}\) \(P\kern{-.8pt}R=62\) 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 \(\sin(\angle P)={58 \over 62}\text{.}\) 1p ○ Hieruit volgt \(\angle P=\sin^{-1}({58 \over 62})\text{.}\) 1p ○ Dus \(\angle P≈69{,}3\degree\text{.}\) 1p 3p d Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(B\kern{-.8pt}C=70\text{,}\) \(\angle C=57\degree\) en \(\angle A=90\degree\text{.}\) Cosinus (1) 007j - Sinus, cosinus en tangens - basis - 0ms d Cosinus in \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) geeft \(\cos(\angle C)={A\kern{-.8pt}C \over B\kern{-.8pt}C}\) ofwel \(\cos(57\degree)={A\kern{-.8pt}C \over 70}\text{.}\) 1p ○ Hieruit volgt \(A\kern{-.8pt}C=70⋅\cos(57\degree)\text{.}\) 1p ○ Dus \(A\kern{-.8pt}C≈38{,}1\text{.}\) 1p opgave 23p a Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(A\kern{-.8pt}C=25\text{,}\) \(\angle C=31\degree\) en \(\angle A=90\degree\text{.}\) Cosinus (2) 007k - Sinus, cosinus en tangens - basis - 0ms a Cosinus in \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) geeft \(\cos(\angle C)={A\kern{-.8pt}C \over B\kern{-.8pt}C}\) ofwel \(\cos(31\degree)={25 \over B\kern{-.8pt}C}\text{.}\) 1p ○ Hieruit volgt \(B\kern{-.8pt}C={25 \over \cos(31\degree)}\text{.}\) 1p ○ Dus \(B\kern{-.8pt}C≈29{,}2\text{.}\) 1p 3p b Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(P\kern{-.8pt}Q=23\text{,}\) \(P\kern{-.8pt}R=61\) 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 \(\cos(\angle P)={23 \over 61}\text{.}\) 1p ○ Hieruit volgt \(\angle P=\cos^{-1}({23 \over 61})\text{.}\) 1p ○ Dus \(\angle P≈67{,}8\degree\text{.}\) 1p |