Getal & Ruimte (12e editie) - vwo wiskunde B
'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 \(Q\kern{-.8pt}R=41\text{,}\) \(\angle Q=43\degree\) 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 \(\tan(43\degree)={P\kern{-.8pt}R \over 41}\text{.}\) 1p ○ Hieruit volgt \(P\kern{-.8pt}R=41⋅\tan(43\degree)\text{.}\) 1p ○ Dus \(P\kern{-.8pt}R≈38{,}2\text{.}\) 1p 3p b Gegeven is \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) met \(K\kern{-.8pt}M=28\text{,}\) \(\angle L=51\degree\) 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 \(\tan(51\degree)={28 \over L\kern{-.8pt}M}\text{.}\) 1p ○ Hieruit volgt \(L\kern{-.8pt}M={28 \over \tan(51\degree)}\text{.}\) 1p ○ Dus \(L\kern{-.8pt}M≈22{,}7\text{.}\) 1p 3p c Gegeven is \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) met \(A\kern{-.8pt}B=37\text{,}\) \(B\kern{-.8pt}C=33\) en \(\angle B=90\degree\text{.}\) Tangens (3) 007o - Sinus, cosinus en tangens - basis - 0ms c Tangens in \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) geeft \(\tan(\angle A)={B\kern{-.8pt}C \over A\kern{-.8pt}B}\) ofwel \(\tan(\angle A)={33 \over 37}\text{.}\) 1p ○ Hieruit volgt \(\angle A=\tan^{-1}({33 \over 37})\text{.}\) 1p ○ Dus \(\angle A≈41{,}7\degree\text{.}\) 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 \(A\kern{-.8pt}B=55\text{,}\) \(\angle B=53\degree\) en \(\angle C=90\degree\text{.}\) Sinus (1) 007g - Sinus, cosinus en tangens - basis - 0ms a Sinus in \(\triangle A\kern{-.8pt}B\kern{-.8pt}C\) geeft \(\sin(\angle B)={A\kern{-.8pt}C \over A\kern{-.8pt}B}\) ofwel \(\sin(53\degree)={A\kern{-.8pt}C \over 55}\text{.}\) 1p ○ Hieruit volgt \(A\kern{-.8pt}C=55⋅\sin(53\degree)\text{.}\) 1p ○ Dus \(A\kern{-.8pt}C≈43{,}9\text{.}\) 1p 3p b Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(P\kern{-.8pt}Q=30\text{,}\) \(\angle R=32\degree\) en \(\angle P=90\degree\text{.}\) Sinus (2) 007h - Sinus, cosinus en tangens - basis - 0ms b Sinus in \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) geeft \(\sin(\angle R)={P\kern{-.8pt}Q \over Q\kern{-.8pt}R}\) ofwel \(\sin(32\degree)={30 \over Q\kern{-.8pt}R}\text{.}\) 1p ○ Hieruit volgt \(Q\kern{-.8pt}R={30 \over \sin(32\degree)}\text{.}\) 1p ○ Dus \(Q\kern{-.8pt}R≈56{,}6\text{.}\) 1p 3p c Gegeven is \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) met \(K\kern{-.8pt}M=50\text{,}\) \(K\kern{-.8pt}L=58\) en \(\angle M=90\degree\text{.}\) Sinus (3) 007i - Sinus, cosinus en tangens - basis - 0ms c Sinus in \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) geeft \(\sin(\angle L)={K\kern{-.8pt}M \over K\kern{-.8pt}L}\) ofwel \(\sin(\angle L)={50 \over 58}\text{.}\) 1p ○ Hieruit volgt \(\angle L=\sin^{-1}({50 \over 58})\text{.}\) 1p ○ Dus \(\angle L≈59{,}5\degree\text{.}\) 1p 3p d Gegeven is \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) met \(L\kern{-.8pt}M=71\text{,}\) \(\angle M=38\degree\) 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 \(\cos(38\degree)={K\kern{-.8pt}M \over 71}\text{.}\) 1p ○ Hieruit volgt \(K\kern{-.8pt}M=71⋅\cos(38\degree)\text{.}\) 1p ○ Dus \(K\kern{-.8pt}M≈55{,}9\text{.}\) 1p opgave 23p a Gegeven is \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) met \(P\kern{-.8pt}R=21\text{,}\) \(\angle R=31\degree\) en \(\angle P=90\degree\text{.}\) Cosinus (2) 007k - Sinus, cosinus en tangens - basis - 0ms a Cosinus in \(\triangle P\kern{-.8pt}Q\kern{-.8pt}R\) geeft \(\cos(\angle R)={P\kern{-.8pt}R \over Q\kern{-.8pt}R}\) ofwel \(\cos(31\degree)={21 \over Q\kern{-.8pt}R}\text{.}\) 1p ○ Hieruit volgt \(Q\kern{-.8pt}R={21 \over \cos(31\degree)}\text{.}\) 1p ○ Dus \(Q\kern{-.8pt}R≈24{,}5\text{.}\) 1p 3p b Gegeven is \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) met \(K\kern{-.8pt}L=35\text{,}\) \(K\kern{-.8pt}M=57\) en \(\angle L=90\degree\text{.}\) Cosinus (3) 007l - Sinus, cosinus en tangens - basis - 0ms b Cosinus in \(\triangle K\kern{-.8pt}L\kern{-.8pt}M\) geeft \(\cos(\angle K)={K\kern{-.8pt}L \over K\kern{-.8pt}M}\) ofwel \(\cos(\angle K)={35 \over 57}\text{.}\) 1p ○ Hieruit volgt \(\angle K=\cos^{-1}({35 \over 57})\text{.}\) 1p ○ Dus \(\angle K≈52{,}1\degree\text{.}\) 1p |