What is the distance between the following polar coordinates?: (7,5π4),(2,9π8)

2 Answers
Apr 4, 2016

P1P2=5328cos(π8)5.209

Explanation:

P1P2=r21+r222r1r2cos(θ2θ1)
r1=7,θ1=5π4;r2=2,θ2=9π8
P1P2=72+22272cos(9π85π4)
P1P2=49+428cos(π8)
P1P2=5328cos(π8)5.209

Apr 4, 2016

s5,27

Explanation:

r1=7
r2=2
θ1=5π4
θ2=9π8
θ2θ1=9π85π4=9π10π8=π8

cos(π8)=0,9

s=r21+r222r1r2cos(θ2θ1)

s=72+222720,9

s=49+4280,9

s=5325.2

s=27,8
s5.27