Ask your own question, for FREE!
Mathematics 8 Online
OpenStudy (darkbluechocobo):

Help with Polar coordinates

OpenStudy (darkbluechocobo):

Convert the rectangular coordinate (-3, 4) to polar coordinates.

OpenStudy (darkbluechocobo):

So tan^-1(4/3)= 53.13 degrees, but our points are in the 2nd quadrant would we add 180?

OpenStudy (johnweldon1993):

So we need R and theta \[\large r = \sqrt{x^2 + y^2}\] \[\large \theta = \tan^{-1}(\frac{y}{x})\]

OpenStudy (darkbluechocobo):

r=sqrt(-3)^2+(4)^2 r=sqrt(9+16) r=sqrt25 r=5

OpenStudy (johnweldon1993):

Right, your R = 5 As far as the angle...remember its actually \(\large tan^{-1}(\frac{4}{-3})\) so you would have -53.13 degrees right?

OpenStudy (er.mohd.amir):

x=r cos t and y=r sin t put find valve of r by square and add by divide find angle polar coordinate is (r,t)

OpenStudy (darkbluechocobo):

Indeed, but I was confused with this example in my text

OpenStudy (darkbluechocobo):

Oh wait nvm I understand now negative / negative = positive *facepalm*

OpenStudy (johnweldon1993):

Yeah lol dont worry about it :D

OpenStudy (darkbluechocobo):

so in this case would we still add 180 to get back to the second quadrant?

OpenStudy (johnweldon1993):

Correct!

OpenStudy (darkbluechocobo):

180+-53.13=126.87 degrees which almost looks like |dw:1431884039075:dw|

OpenStudy (johnweldon1993):

Yeah good enough! lol So we have \[\large (5, 126.87^\circ)\]

OpenStudy (darkbluechocobo):

Indeedly It almost went smoothly besides my failure to recognize 4/-3

OpenStudy (johnweldon1993):

Lol no problem, mistakes happen!

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!