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,/<+;+8 .+8 +;+2 +.3 ,/<+;+8 ?/5=9; +.+6+2 ,/<+;+8 B+81 7/736353 (a)
,/<+; 836+3 .+8 4>1+ +;+2 98=92 ,/<+;+8 ?/5=9; .3 +8=+;+8B+ 5/
-/:+=+8 :/;-/:+=+8 1+B+ 797/8=>7 .+8 :/;:38.+2+8 40 N arah kanan
(b)
a. Menggambarkan Vektor
'/,>+2 ?/5=9; .31+7,+;5+8 ./81+8 </,>+2 +8+5 :+8+2 B+81 =/;.3;3 Gambar 2.1 50 N arah kiri
+=+< :+815+6 ?/5=9; :+84+81 ?/5=9; .+8 +;+2 ?/5=9; ;+2 +8+5 :+8+2 383 Panjang vektor a adalah 40 N dan
7/8>84>55+8 836+3 +=+> 2+;1+ ?/5=9; =/;</,>= '/7+538 :+84+81 1+7,+; vektor b adalah 50 N. Satu satuan skala
</,>+2 ?/5=9; </7+538 ,/<+; 836+3 ?/5=9; =/;</,>= 1+; 6/,32 4/6+< pada vektor a dab b besarnya 10 N.
:/;2+=35+8 +! / .+8 +! / ,/;35>= arah
vektor
pangkal
b. Penulisan Notasi Besaran Vektor vektor
#9=+<3 ,/<+;+8 ?/5=9; .+:+= ,/;>:+ 2>;>0 5+:3=+6 +=+> 2>;>0 5/-36 panjang
vektor
)8=>5 =>63<+8 =+81+8 89=+<3 =/;</,>= ,/;>:+ 2>;>0 B+81 .3,/;3 =+8.+ Gambar 2.2

:+8+2 .3 +=+<8B+ 73<+68B+ A +=+> a )8=>5 =>63<+8 -/=+5 89=+<3 =/;</,>= Sebuah vektor
,3+<+8B+ .3-/=+5 =/,+6 73<+68B+ .+8
#36+3 ?/5=9; >8=>5 =>63<+8 -/=+5 .38B+=+5+8 ./81+8 2>;>0 =3:3< 73 A
;381 73<+68B+ >8=>5 =>63<+8 =+81+8 836+3 ?/5=9; .38B+=+5+8 ./81+8 B
2>;>0 =+8:+ =+8.+ :+8+2 73<+68B+
>+ ?/5=9; .3</,>= <+7+ ,/<+; 435+ ,/<+; .+8 +;+28B+ <+7+ %/;2+=35+8 D
+! / */5=9; <+7+ ./81+8 ?/5=9; 5+;/8+ 5/.>+ ?/5=9; 7/736353 C
,/<+; .+8 +;+2 B+81 <+7+ </.+815+8 ?/5=9; .+8 ?/5=9; ,/;,/.+
5+;/8+ 5/.>+ ?/5=9; =/;</,>= 7/736353 +;+2 B+81 ,/;,/.+ */5=9; .3</,>= Gambar 2.3
Contoh beberapa vektor, vektor
6+@+8 .+;3 ?/5=9; 5+;/8+ ,/<+;8B+ <+7+ =/=+:3 +;+28B+ ,/;6+@+8+8 A = vektor B.

2. Penjumlahan dan Selisih Vektor
a. Penjumlahan Vektor B
>+ ?/5=9; +=+> 6/,32 .+:+= .34>76+25+8 +=+> .35>;+815+8 +<36
:/84>76+2+8 +=+> :/81>;+81+8 .3</,>= ;/<>6=+8 ?/5=9; )8=>5 7/81
23=>81 ;/<>6=+8 ?/5=9; B+81 ,/;,/.+ :+.+ <+=> ,3.+81 .+:+= .31>8+5+8
.>+ 7/=9./ B+3=> 7/=9./ 4+4+;1/84+81 .+8 7/=9./ :963198 C
$,(2+* & , 3$)1-/ #$,% , +$1-#$ ( ( /%$,( ,%
>+ ,>+2 ?/5=9; +=+> 6/,32 .+:+= .34>76+25+8 ./81+8 7/6>53< A
</,>+2 4+4+;1/84+81 ./81+8 5/.>+ ?/5=9; =/;</,>= </,+1+3 <3<3 <3<38B+ O
.+:>8 ;/<>6=+88B+ .3:/;96/2 .+;3 .3+198+6 4+4+;1/84+81 B+3=> =3=35 R = D + C
:+815+68B+ <+7+ ./81+8 5/.>+ =3=35 :+815+6 ?/5=9; =/;</,>= %/;2+=35+8 D = A + B
+! / .+8 +! / B

B B

C
R

A
O
O A O A Gambar 2.5
Resultan tiga buah vektor, yaitu
Gambar 2.4 R = A + B + C yangdiperoleh
R adalah vektor resultan dari vektor A dan B dengan metode jajargenjang.
$,(2+* & , 3$)1-/ #$,% , +$1-#$ .-*'%-, 0$%' ! ,6 )
&/<>6=+8 .+;3 :/84>76+2+8 .>+ ?/5=9; +=+> 6/,32 .3:/;96/2 ./81+8
7/738.+25+8 :+815+6 ?/5=9; B+81 <+=> 5/ >4>81 ?/5=9; B+81 6+38
./7353+8 </=/;><8B+ .+:>8 ?/5=9; 2+<36 :/84>76+2+8 ;/<>6=+8 .3
:/;96/2 ./81+8 7/812>,>815+8 :+815+6 ?/5=9; :/;=+7+ 5/ >4>81 ?/5=9;
=/;+523; %/;2+=35+8 +! / .+8 +! /

Vektor 33