Find the slope of the tangent line to the graph of the polar equation at the point specified by the value of πœƒ.

r = 1/πœƒ
πœƒ = πœ‹

2 answers

dy/dx = (dr/dπœƒ) / (dx/dπœƒ) = (r' sinπœƒ + r cosπœƒ) / (r' cosπœƒ - r sinπœƒ)
= (-sinπœƒ/πœƒ^2 + cosπœƒ/πœƒ) / (-cosπœƒ/πœƒ^2 - sinπœƒ/πœƒ)
= (-sinπœƒ + r cosπœƒ)/(-cosπœƒ - r sinπœƒ) if πœƒβ‰ 0
at πœƒ=πœ‹, that means
dy/dx = -πœ‹
oops. did you catch my typo?