What is the distance between #(4 ,( 7 pi)/6 )# and #(3 , ( -3 pi )/2 )#?

2 Answers
Oct 3, 2017

#8.44#

Explanation:

Distance #=sqrt((3-4)^2+(((-3pi)/2)-((7pi)/6))^2#
#=sqrt(1+((16pi)/6)^2)#
#=sqrt(1+70.18)=sqrt71.18=8.44 # (as #pi=22/7#)

Oct 4, 2017

Distance between the two points is #4sqrt3#

Explanation:

The polar coordinates #(4,(7pi)/6)# are equivalent to rectangular or Cartesian coordinates #(4cos((7pi)/6),4sin((7pi)/6))# i.e. #(-(4sqrt3)/2,-2)#, and

polar coordinates #(3,-(3pi)/2)# are equivalent to rectangular or Cartesian coordinates #(4cos(-(3pi)/2),4sin(-(3pi)/2))# i.e. #(0,4)#

and distance between the two points is

#sqrt((0-(-(4sqrt3)/2))^2+(4-(-2))^2)#

= #sqrt((2sqrt3)^2+(6)^2)#

= #sqrt(12+36)=sqrt48=4sqrt3#