Q. Find all angles, 0∘≤θ<360∘, that satisfy the equation below, to the nearest tenth of a degree.sin2θ−4sinθ−5=0Answer: θ=
Rewrite Equation: Let's first rewrite the given equation to identify it as a quadratic equation in terms of sin(θ):sin2(θ)−4sin(θ)−5=0We can treat sin(θ) as a variable, say 'u', and rewrite the equation as:u2−4u−5=0
Factor Quadratic: Now, we will factor the quadratic equation:(u−5)(u+1)=0This gives us two possible solutions for u:u−5=0 or u+1=0
Solve for u: Solving for 'u' from both equations, we get:u=5 or u=−1Since 'u' was a stand-in for sin(θ), we now have:sin(θ)=5 or sin(θ)=−1
Check Validity: We know that the sine function has a range of [−1,1], so sin(θ)=5 has no solution because it is outside this range. We only need to consider sin(θ)=−1.
Find Angle: The angle θ that satisfies sin(θ)=−1 within the range of 0 to 360 degrees is: θ=270 degrees
Final Solution: We have found all the angles that satisfy the given equation. Since sin(θ)=5 had no solution, the only angle we found is θ=270 degrees.
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