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Find the exact values of sinθ/2 and cosθ/2 for sinθ = 11/19 on the interval 0° ≤ θ ≤ 90°.

a) Sinθ/2: 11/22, Cosθ/2: 3/22
b) Sinθ/2: 11/19, Cosθ/2: 2/19
c) Sinθ/2: 3/22, Cosθ/2: 11/22
d) Sinθ/2: 2/19, Cosθ/2: 11/19

User Warpzit
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Final answer:

The exact values of sinθ/2 and cosθ/2 for sinθ = 11/19 on the interval 0° ≤ θ ≤ 90° are: Sinθ/2: ±(2/√19), Cosθ/2: ±(√15/√19).

Step-by-step explanation:

To find the exact values of sinθ/2 and cosθ/2 for sinθ = 11/19 on the interval 0° ≤ θ ≤ 90°, we can use the half-angle identities for sine and cosine.

The half-angle identity for sine is: sin(θ/2) = ±√((1 - cosθ)/2)

The half-angle identity for cosine is: cos(θ/2) = ±√((1 + cosθ)/2)

Since sinθ = 11/19, we can substitute this value into the half-angle identities to find sin(θ/2) and cos(θ/2).

sin(θ/2) = ±√((1 - cosθ)/2) = ±√((1 - 11/19)/2) = ±√(8/38) = ±√(4/19) = ±(2/√19)

cos(θ/2) = ±√((1 + cosθ)/2) = ±√((1 + 11/19)/2) = ±√(30/38) = ±√(15/19) = ±(√15/√19)

Therefore, the exact values of sinθ/2 and cosθ/2 for sinθ = 11/19 on the interval 0° ≤ θ ≤ 90° are:

Sinθ/2: ±(2/√19)

Cosθ/2: ±(√15/√19)

User Jenny Blunt
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