Ask your own question, for FREE!
Mathematics 17 Online
OpenStudy (anonymous):

Help! -5i-i/-2+7i

OpenStudy (asnaseer):

you need to turn the denominator into a real number. so, do you what to do to turn (-2+7i) into a real number? (you need to multiply by something)

OpenStudy (anonymous):

multiply top and bottom by -2-7i ?

OpenStudy (asnaseer):

correct

OpenStudy (anonymous):

i got (-5-i)(-2-7i)/53

OpenStudy (asnaseer):

you should be able to multiply out the numerator as well and simplify further

OpenStudy (anonymous):

so i guess if u foil the top then u'll get 10+35i+2i+7i^2

OpenStudy (anonymous):

i don't get this part

OpenStudy (anonymous):

10+37i+7i^2

OpenStudy (asnaseer):

remember i^2 = -1

OpenStudy (anonymous):

oh yeah

OpenStudy (anonymous):

would it be 3+37i ?

OpenStudy (asnaseer):

correct - but don't forget the denominator

OpenStudy (anonymous):

oh yea

OpenStudy (asnaseer):

:)

OpenStudy (anonymous):

so i guess it just 3+37i/53 ?

OpenStudy (asnaseer):

thats it - well done!

OpenStudy (anonymous):

thank you !!

OpenStudy (asnaseer):

yw

Can't find your answer? Make a FREE account and ask your own questions, OR help others and earn volunteer hours!

Join our real-time social learning platform and learn together with your friends!
Can't find your answer? Make a FREE account and ask your own questions, OR help others and earn volunteer hours!

Join our real-time social learning platform and learn together with your friends!