The normal at P₁(4,2) on the curve xy = 8 meets the curve again at P₂, then normal at P₂ meets the curve in P₃ and so on, then
₉₉
a) slope of normal at P₁₀₀ is 2³
₉₉
b) slope of normal at P₁₀₀ is 1/2³
c) if chord joining P₁ and P₄ subtends right angel at point Q on curve, then slope of normal at Q is 2¹³
₈
d) slope of tangent at P₉ is 1/2³