What is the distance between #(4 ,( - pi)/8 )# and #(-1 ,( 3 pi )/2 )#? Trigonometry The Polar System Polar Coordinates 1 Answer Bdub Apr 15, 2016 #P_1P_2~~4.47# Explanation: Use formula #P_1P_2=sqrt(r_1^2+r_2^2-2r_1r_2cos(theta_2-theta_1))# #r_1=4,theta_1=-pi/8 and r_2=-1,theta_2=(3pi)/2# #P_1P_2=sqrt(4^2+(-1)^2-2(4)(-1)cos(((3pi)/2)-(-pi)/8)# #=sqrt(16+1+8cos((13pi)/8)# #=sqrt(17+8cos((13pi)/8))# #P_1P_2~~4.47# Answer link Related questions What are Polar Coordinates? How do you find the polar coordinates of the point? What is the difference between a rectangular coordinate system and a polar coordinate system? How do you graph polar coordinates? What careers use polar coordinates? How do you plot the point #A (5, -255^\circ)# and the point #B (3, 60^\circ)#? What does a polar coordinate system look like? How do you find the distance between 2 polar coordinates? For the given point #A(-4, frac{pi}{4})#, how do you list three different pairs of polar... How do you find the rectangular form of #(4, -pi/2)#? See all questions in Polar Coordinates Impact of this question 1437 views around the world You can reuse this answer Creative Commons License