Solve, for 0 ≤ θ < 360 , the equation sin2 θ = 1 + cos θ

Mathematics

1 answer:

marshall27 [118]3 years ago

3 0

Answer:

θ = 90°, 180°, or 270°

Step-by-step explanation:

sin²θ = 1 + cos θ

Use Pythagorean identity.

1 − cos²θ = 1 + cos θ

Move everything to one side and simplify.

0 = cos²θ + cos θ

Factor.

0 = cos θ (cos θ + 1)

Solve.

cos θ = 0 or -1

θ = 90°, 180°, or 270°

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3 years ago

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PLS HELP NOW!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

kupik [55]

The correct answers are:

1. 35

2. B.) Rational

3. -88/3 or as a decimal, 29.3 repeating

4. 226.981

5. -6

Hope This Helps!!!