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Given sin(θ) = 7/8, and θ lies in quadrant II, find θ.

User Mukta
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Final answer:

To find the angle θ given sin(θ) = 7/8 and θ is in the second quadrant, calculate the reference angle with arcsin(7/8) and then subtract from 180° because sine is positive in the second quadrant. Thus, θ is approximately 119°.

Step-by-step explanation:

The student's question asks how to find the angle θ given that sin(θ) = 7/8, with θ in the second quadrant. To find θ, we will use the inverse sine function, also known as arcsin. However, since θ is in the second quadrant, we must consider the principle that sine is positive in the first and second quadrants, and the range of the arcsin function is from -90° to 90°.

First, find the reference angle α in the first quadrant such that sin(α) = 7/8:

α = arcsin(7/8)

Since a calculator is typically used for this, assume α ≈ 61° given the range of arcsin.

Now, because θ is in the second quadrant, we calculate θ as 180° - α:

θ = 180° - 61° = 119°

Therefore, the angle θ is approximately 119°.

User SelftaughtMonk
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