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2 trig questions please help?

if theta is any real number, is it possible for sin(theta) = 5/4? Why or why not?

if theta is any real number, is it possible for sin(theta) = 0.25 and cos(theta) = 0.5? Why or why not?

4 Answers

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  • xyzzy
    Lv 7
    6 years ago
    Favorite Answer

    think about what sin x and cos x represent in your unit circle.

    Is there a point on a circle of radius 1 that more than 1 units away?

    or less than 1 unit away?

  • coreyA
    Lv 6
    6 years ago

    First question for any real θ, sin(θ) ranges between 1 and -1. Since 5/4 is not in that interval, there is no real θ, that satisfies sin(θ) = 5/4.

    Second question, for all real θ, sin²(θ) + cos²(θ) = 1. (.25)² + (.5)² = .0625 + .25 ≠ 1. So you can not have sin(θ) = 0.25 and cos(θ) = 0.5.

  • 6 years ago

    if theta is any real number, is it possible for sin(theta) = 5/4? Why or why not?

    It is not possible because - 1 </= sin(theta) </= 1

    if theta is any real number, is it possible for sin(theta) = 0.25 and cos(theta) = 0.5? Why or why not

    It is not possible

    If sin(theta) = 0.25 then cos(theta) = Sqrt(3)/4 and

    if cos(theta) = 0.5 then sin(theta) = sqrt(3)/2

  • DWRead
    Lv 7
    6 years ago

    No. The range of sine is [-1,1].

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