Question

given (x,y) what is (r,theta)?

Answer 1

r=\[\sqrt{x ^{2}+y ^{2}}\]
\[\theta=\tan^{-1} (y/x)\]

Answer 2

\[x= -\sqrt{3} \] y=1
r=\[\sqrt{x ^{2}+y ^{2}}=2\]
\[\theta=\tan^{-1} \frac{ 1 }{ -\sqrt{3} }\]= -30°
but \[\theta \]'s absoluet value should be the least and the answer in the book is 150° but idk how

Answer 3

150 seems to be incorrect,because -30 lies in 4th quadrant and equals 360-30=330 degrees , and if u want least absolute value its -30 only

Answer 4

i don't know the book said 150° :(

Answer 5

i guess its wrong.. thx anyway :)

Answer 6

well,as per my thoughts now, they have used that tan has period of 180 degres
that is tan(theta)=tan (180+ theta)
so tan (-30)=tan(180-30)=tan 150