What is the distance between (5 ,( pi)/4 )(5,π4) and (3 , (11 pi )/12 )(3,11π12)?

1 Answer
May 25, 2016

The distance is sqrt(19)19.

Explanation:

I asume that your two points are in polar coordinates.
If so, we have the two points:

r_1=5, theta_1=pi/4r1=5,θ1=π4
r_2=3, theta_2=11/12pir2=3,θ2=1112π

the distance of two points in polar coordinates is given by

d=sqrt(r_1^2+r_2^2-2r_1r_2cos(theta_1-theta_2))d=r21+r222r1r2cos(θ1θ2)

for you this is

d=sqrt(5^2+3^2-2*3*5*cos(pi/4-11/12pi))d=52+32235cos(π41112π)
d=sqrt(25+9-30cos(-2/3pi))d=25+930cos(23π)
d=sqrt(34-30cos(2/3pi))d=3430cos(23π)
d=sqrt(34-30*1/2)d=343012
d=sqrt(19)d=19