anonymous
  • anonymous
please simplify step by step (8+i)(2+7i)
Mathematics
  • Stacey Warren - Expert brainly.com
Hey! We 've verified this expert answer for you, click below to unlock the details :)
SOLVED
At vero eos et accusamus et iusto odio dignissimos ducimus qui blanditiis praesentium voluptatum deleniti atque corrupti quos dolores et quas molestias excepturi sint occaecati cupiditate non provident, similique sunt in culpa qui officia deserunt mollitia animi, id est laborum et dolorum fuga. Et harum quidem rerum facilis est et expedita distinctio. Nam libero tempore, cum soluta nobis est eligendi optio cumque nihil impedit quo minus id quod maxime placeat facere possimus, omnis voluptas assumenda est, omnis dolor repellendus. Itaque earum rerum hic tenetur a sapiente delectus, ut aut reiciendis voluptatibus maiores alias consequatur aut perferendis doloribus asperiores repellat.
schrodinger
  • schrodinger
I got my questions answered at brainly.com in under 10 minutes. Go to brainly.com now for free help!
anonymous
  • anonymous
we just cross multiply. to get 16+56i+2i+7i^2. then we just combine like terms to get 16+58i+7i^2
anonymous
  • anonymous
i thought so too but its wrong..
anonymous
  • anonymous
the answer is 56i+9 but idk how.

Looking for something else?

Not the answer you are looking for? Search for more explanations.

More answers

anonymous
  • anonymous
no that answer is wrong.
anonymous
  • anonymous
i checked on mathway
EarthCitizen
  • EarthCitizen
\[j ^{2}=-1 \therefore (8+j)(2+j7) = 16+j56+j2-7 = j58-9\]
anonymous
  • anonymous
|dw:1332994349758:dw|
anonymous
  • anonymous
thank u juanita!!
anonymous
  • anonymous
actually just use FOIL method to do this. i^2 = -1
anonymous
  • anonymous
uw
EarthCitizen
  • EarthCitizen
sorry, typo that's j58+9
anonymous
  • anonymous
wait so 7^2 = -7, oh wtf lol
anonymous
  • anonymous
7i^2
EarthCitizen
  • EarthCitizen
yep
anonymous
  • anonymous
same thing with i^3? equals its opposite coefficient sign?
anonymous
  • anonymous
= -i
EarthCitizen
  • EarthCitizen
\[j ^{3} = -j\]
anonymous
  • anonymous
what do u mean? give me an example please.
anonymous
  • anonymous
55i^3 = -55?
EarthCitizen
  • EarthCitizen
\[j= \sqrt{-1} \therefore j ^{3}= (\sqrt{-1})*(\sqrt{-1})*(\sqrt{-1}) = -(\sqrt{-1}) = -j\]
EarthCitizen
  • EarthCitizen
\[j ^{3}55=-j55\]
anonymous
  • anonymous
ok i see now thanks!!
EarthCitizen
  • EarthCitizen
no p!
anonymous
  • anonymous
man algebra 2 is so hard lol. too much stuff to remember.
EarthCitizen
  • EarthCitizen
is this algebra ? thought it was complex variables
anonymous
  • anonymous
lol algebra is the coarse im taking. complex variables is what we are learning right now, i was just saying in general that algebra is hard because its so confusing since you have to remember a lot of stuff lol.
EarthCitizen
  • EarthCitizen
lol, fair enough
anonymous
  • anonymous
so did u pass algebra 2?
anonymous
  • anonymous
what are u taking right now?
EarthCitizen
  • EarthCitizen
mechanical engineering; engineering maths, solid mechanics, thermofluids and electrical science
anonymous
  • anonymous
lol wow so this basically is simple stuff for you?
EarthCitizen
  • EarthCitizen
well, with practice it gets a lot easier. No, it wasn't easy at first
anonymous
  • anonymous
lol true but i just dont see how I will apply this to real life lol.
EarthCitizen
  • EarthCitizen
complex variables is a tremendous invention. Listen to Richard Feynman's "Basics of Physics" he describes the nature of physics to the real world. Basically, reality can only be described by mathematics, mathematics is the real world
anonymous
  • anonymous
oh i see. I take physics next year =p and precalculus, btw is precalculous harder than algebra 2? o-o
EarthCitizen
  • EarthCitizen
I'm sorry these are elementary subjects so they're quite basic. This is not deep at all, both subjects are basic which I studied in high school.
anonymous
  • anonymous
oh dam really? what grade are u in if u dont mind me asking lol
EarthCitizen
  • EarthCitizen
Year 1
anonymous
  • anonymous
cool im smarter than u =D
EarthCitizen
  • EarthCitizen
no p
anonymous
  • anonymous
u said year 1, im year 11 =D
anonymous
  • anonymous
which makes me higher level?
EarthCitizen
  • EarthCitizen
lol, Year 1 in british system means First Year or Freshman Uni
anonymous
  • anonymous
ur british?
EarthCitizen
  • EarthCitizen
yep
anonymous
  • anonymous
oh cooooooooooool
EarthCitizen
  • EarthCitizen
yh
anonymous
  • anonymous
well nice chatting with u lol
EarthCitizen
  • EarthCitizen
same here
anonymous
  • anonymous
bye.. :)

Looking for something else?

Not the answer you are looking for? Search for more explanations.