Question

ρ²=a/cos2θ化为直角坐标方程？

Answer 1

ρ²=a/cos2θ
==> ρ²cos2θ=a
==> ρ²·(cos²θ-sin²θ)=a
==> (ρcosθ)²-(ρsinθ)²=a
==> x²-y²=a

Answer 2

p^2=a/cos2θ
p^2cos2θ=a
p^2x2sⅰnθcosθ=a
2psⅰnθpcosθ=a
2xy=a。