<u>Answer and explanation</u>
(1+sinθ)(1-sinθ)=cos²θ
We are to prove that the left hand side is equal to the right hand side.
(1+sinθ)(1-sinθ) = 1(1-sinθ) + sinθ(1-sinθ)
= 1 - sinθ + sinθ - sin²θ
= 1 - sin²θ
From the trigonometric identity sin²θ + cos²θ = 1,
1 - sin²θ = cos²θ
If you have these conditions:
1. (r ,theta) where r > 0
<span>2. (r, theta) where r < 0
</span>
The solution would be:
<span>r = sqrt(x^2 + y^2)
t = arctan(y/x)
r = sqrt(12 + 4) = sqrt(16) = +/- 4
t = arctan(2 / -2sqrt(3)) = arctan(-1 / sqrt(3)) = 5pi/6 , 11pi/6
1)
r > 0
(4 , 11pi/6)
2)
r < 0
(-4 , 5pi/6)
</span>
I hope my answer has come to your help. Thank you for posting your question here in Brainly. We hope to answer more of your questions and inquiries soon. Have a nice day ahead!
