SOLUTION: Please help me with this Calculus II question: Find all points of intersection of the given curves. (Assume 0 ≤ θ ≤ 2π. Order your answers from smalles

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Question 809615: Please help me with this Calculus II question:
Find all points of intersection of the given curves. (Assume
0 ≤ θ ≤ 2π.
Order your answers from smallest to largest θ. If an intersection occurs at the pole, enter POLE in the first answer blank.)
r = 1 − cos θ, r = 1 + sin θ

Answer by Edwin McCravy(20056) About Me  (Show Source):
You can put this solution on YOUR website!
Please help me with this Calculus II question:
Find all points of intersection of the given curves. (Assume
0 ≤ θ ≤ 2π.
Order your answers from smallest to largest θ. If an intersection occurs at the pole, enter POLE in the first answer blank.)
r = 1 − cos θ, r = 1 + sin θ
 1 − cos θ = 1 + sin θ  , since both = r
    −cos θ = sin θ
Divide both sides by cos θ
   %28-cos%28theta%29%29%2Fcos%28theta%29 = sin%28theta%29%2Fcos%28theta%29
   -1 = tan(θ)

   
So θ has two possible values where 0 ≤ θ ≤ 2π. the tangent is negative
in Q2 and Q4 and the reference angle is 45° or pi%2F4, so θ is 3pi%2F4
in Q2 or 7pi%2F4 in Q4.
 
So the smaller value of θ is 3pi%2F4, and the value of r is gotten
by substituting 3pi%2F4 for θ in either of the original equations:
r = 1 − cos θ = 1 - cos%283pi%2F4%29 = 1 - %28-sqrt%282%29%2F2%29 = 1 + sqrt%282%29%2F2 = %282%2Bsqrt%282%29%29%2F2
So the first point is (r,θ) = (%282%2Bsqrt%282%29%29%2F2, 3pi%2F4)
The larger value of θ is 7pi%2F4, and the value of r is gotten
by substituting 7pi%2F4 for θ in either of the original equations:
r = 1 − cos θ = 1 - cos%287pi%2F4%29 = 1 - %28sqrt%282%29%2F2%29 = 1 - sqrt%282%29%2F2 = %282-sqrt%282%29%29%2F2
So the second point is (r,θ) = (%282-sqrt%282%29%29%2F2, 7pi%2F4)

Edwin