Question Number 103859 by 175mohamed last updated on 17/Jul/20

           solve :        y^2  + x^2  = −sin(θ)     .,    (π/2)≥ θ≥−(π/2)

Answered by mathmax by abdo last updated on 18/Jul/20

if x and y from C let x =rcosα and y =r sinα  e ⇒r^2  =−sinθ   but r>0 (radius) ⇒sinθ<0 ⇒−(π/2)<θ<0 ⇒  r =(√(−sinθ)) ⇒x =(√(−sinθ))cos(α) and y =(√(−sinθ))sin(α)  and ∈]0,2π[  if sinθ>0 →no solution...

Commented bymathmax by abdo last updated on 18/Jul/20

sorry x and y from R..