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yessir
yessir asked in Science & MathematicsMathematics · 12 months ago

will award best answer circular functions help?

if: pi < θ < 3pi/2 and sinθ = -2/3, find sin20

a) -4sqrt5/9

b) -4/3

c) 1/3

d) 4sqrt5/9

1 Answer

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  • rotchm
    Lv 7
    12 months ago
    Favorite Answer

     sin(2θ) = 2 sin(θ)cos(θ), right?

    You are given sin(θ) and you are told in what quadrant θ is.

    Thus, what is the value of cos(θ)? Then just compute 2 sin(θ)cos(θ).

    Done!

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