Anonymous
Anonymous asked in Education & ReferenceHomework Help · 1 month ago

Unit circle help?

My answer was an educated guess. 

Update:

I submitted the -1/2 and received a 2/3. I guess one of the parts of the question are wrong. Not sure which one. This question does not have the option of choosing a square root sign, only whole numbers... the first drop down is either a - or +, and the other two are numbers 1, 2, and 3

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  • Anonymous
    1 month ago

    The angle is 45 and exact value of cos(45°) is √(2) / 2.

    They already give you the square root sign, so the drop downs are both 2

    As the quadrant includes -1, the valency should also be minus.

  • 1 month ago

    tan 𝜽 = opp/adj

    On the unit circle in QII

    tan 𝜽 = -1 = 1 / (-1)

    opp = 1

    adj = -1

    hyp = √(opp² + adj²)

    hyp = √( 1² + (-1)² )

    hyp = √ 2

    Cos 𝜽 = adj / hyp

    cos 𝜽 = -1/√2

    Rationalizing the denominator

    cos 𝜽 = -√2 / 2 <––––––

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