Problem:The parametric curve r = (–t^2 – 4t – 4, –3cos(πt), t^3 – 28t) crosses itself at one and only one point P.a) What are the coordinates of this point P?b) Letting θ be the acute angle between the two tangent lines to the curve at the crossing point, what is the value of cos(θ)?Answers:a) P(–16,–3,–48)b) cos(θ) = 0.934487734928968I'm trying to follow this link ( Pauls Online Notes : Calculus II - Tangents with Parametric Equations ), but I'm having trouble adapting that to this particular problem.Could someone please tell me how to go about solving this problem?