Consider the two vectors a(with arrow above)=5i-3j and b(with arrow above)=-i-2j

1. calculate a (with arrow above) + b (with arrow above)
2. calculate a (with arrow above) - b (with arrow above)
3. calculate absolute value of a (with arrow above) + b (with arrow above)
4. calculate absolute value of a (with arrow above) - b (with arrow above)
5. calculate the directions of a (with arrow above) + b (with arrow above) and a (with arrow above) - b (with arrow above).
(answers are counterclockwise from the +xaxis)

A= 5 i − 3 J and B = −i − 6 j 

A+ B 
=5 i − 3 j −i − 6 j = 4 i - 9 j ---answer 

A - B 
= 5 i − 3 j + i + 6 j = 6 i + 3j ---answer 

|A+B| 
= sq root [ 16 + 81] = 9.848 ---answer 

|A - B| 
= sq root [ 36 + 9] = 6.708 ---answer 

directions of A+ B 
= tan (-1) -9 /4 = - 66 deg --answer 

direction of A- B 
= tan (-1) 3 /6 = 26.56 deg --answer

Acetic acid  /əˈsiːtɪk/, systematically named  ethanoic acid  /ˌɛθəˈnoʊɪk/, is a colourless liquid  organic compound  with the  chemical formula  ch3cooh (also written as ch3co2h or c2h4o2). when undiluted, it is sometimes called  glacial acetic acid.  vinegar  is no less than 4% acetic acid by volume, making acetic acid the main component of vinegar apart from water. acetic acid has a distinctive sour taste and pungent smell. in addition to household vinegar, it is mainly produced as a precursor to  polyvinyl acetate  and  cellulose acetate. it is classified as a  weak acid  since it only partially  dissociates  in solution, but concentrated acetic acid is corrosive and can attack the skin.acetic acidnamespreferred iupac nameacetic acidsystematic iupac nameethanoic acidother namesvinegar (when dilute); hydrogen acetate; methanecarboxylic acid[1][2]identifierscas number64-19-7  3d model (jsmol)interactive image3dmetb00009 reference506007chebichebi: 15366  chemblchembl539  chemspider171  drugbankdb03166  echa infocard100.000.528ec number200-580-7e numbere260  (preservatives)gmelin reference1380iuphar/bps1058keggd00010  meshacetic+acidpubchem  cid176rtecs numberaf1225000uniiq40q9n063p  un number2789inchiinchi=1s/c2h4o2/c1-2(3)4/h1h3,(h,3,4)  key:   qtbsbxvteameqo-uhfffaoysa-n  smilescc(o)=o