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Given: Sin Ø = 2/3 and Ø is in the second quadrant; evaluate the following expression. Sin2Ø

Please explain!!

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Answer: The formula for sin2θ is sin2θ = 2sinθcosθ. We know that sinθ = 2/3. To evaluate cosθ, we use the fact that in the second quadrant, cosθ is negative. Therefore, cosθ = -sqrt(1-sin2θ). Plugging in the value of sinθ and simplifying, we get cosθ = -sqrt(7/9).

Finally, we can substitute the values of sinθ and cosθ into the formula for sin2θ to get: sin2θ = 2(2/3)(-sqrt(7/9)) = -4/3.
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