Convert the point (x,y,z)=(-3,-5,-1) to cylindrical coordinates. Give r and θ as positive values, either as expressions, or decimals to at least one decimal place. (r,theta,z)
r = sqrt( (-3)2 + (-5)2 + (-1)2 ) → 5.916
θ = tan-1(-5/-3) + pi → 4.172 radians (or 239.036°) measured anticlockwise from the positive x-axis.
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