What is the polar form of #( 11,-9 )#?

1 Answer
hev1
Mar 22, 2018

The polar form of the coordinate pair #(11, -9)# is #(sqrt(202), -39.289)#.

Explanation:

The polar form of a coordinate pair #(x, y)# is #(r, theta)#.
To find r, we use the formula #r^2 = x^2+y^2#.
#r^2 = 11^2 + (-9)^2#
#r^2 = 121 + 81#
#r^2 = 202#
#r = sqrt(202)#
#r ~~ 14.21#
To find #theta#, we use the formula #y/x = tan(theta)#.
#(-9)/11 = tan(theta)#
#theta = tan^-1((-9)/11)#
#theta ~~ tan^-1(0.818182)#
#theta ~~ -39.289407#

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