Q. The angle θ1 is located in Quadrant II, and cos(θ1)=−1912.What is the value of sin(θ1) ? Express your answer exactly.sin(θ1)=
Pythagorean identity: We know that for any angle θ, sin2(θ)+cos2(θ)=1 (Pythagorean identity).Given that cos(θ1)=−1912, we can find sin(θ1) by rearranging the Pythagorean identity to solve for sin2(θ1).sin2(θ1)=1−cos2(θ1)
Rearranging the Pythagorean identity: Substitute the given value of cos(θ1) into the equation.sin2(θ1)=1−(−(1912))2sin2(θ1)=1−(361144)
Substituting the given value: Simplify the right side of the equation.sin2(θ1)=361361−361144sin2(θ1)=361361−144sin2(θ1)=361217
Simplifying the equation: Take the square root of both sides to find sin(θ1). Since θ1 is in Quadrant II, sin(θ1) is positive.sin(θ1)=361217sin(θ1)=19217
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