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Math Help - Radian question with integral

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    Radian question with integral

    I think I am making a silly error:

    They say: "we know the angle arcsin((radical3)/2) equals the angle between [-pi/2,pi/2] who sine is (radical3)/2


    This angle is 60 radians


    Apparently 60 is wrong, but I thought sin60 is radical3/2. Are they asking for the values of arcsin60? Amateur question but I'm confused as to what they want.
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  2. #2
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    Re: Radian question with integral

    Quote Originally Posted by Steelers72 View Post
    I think I am making a silly error:
    They say: "we know the angle arcsin((radical3)/2) equals the angle between [-pi/2,pi/2] who sine is (radical3)/2
    This angle is 60 radians
    Apparently 60 is wrong, but I thought sin60 is radical3/2. Are they asking for the values of arcsin60? Amateur question but I'm confused as to what they want.
    Yes that is wrong.
    \arcsin\left(\frac{\sqrt{3}}{2}\right)=\frac{\pi}{  3}
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    Re: Radian question with integral

    Quote Originally Posted by Steelers72 View Post
    I think I am making a silly error:

    They say: "we know the angle arcsin((radical3)/2) equals the angle between [-pi/2,pi/2] who sine is (radical3)/2


    This angle is 60 radians


    Apparently 60 is wrong, but I thought sin60 is radical3/2. Are they asking for the values of arcsin60? Amateur question but I'm confused as to what they want.

    You are giving the answer in degrees not radians

    \sin(60^\circ)=\frac{\sqrt{3}}{2}

    In radians this gives

    \sin\left( \frac{\pi}{3}\right)=\frac{\sqrt{3}}{2}
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    Re: Radian question with integral

    Thank you both. Silly error. 180/3 =60 but in radians it has a pi. Bless!
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    Re: Radian question with integral

    It asks to do 3arcsin(radical3/2) - 3arcsin(1/2)

    I got 90. Is this correct?
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    Re: Radian question with integral

    Quote Originally Posted by Steelers72 View Post
    It asks to do 3arcsin(radical3/2) - 3arcsin(1/2)
    I got 90. Is this correct?
    Give up the use of degrees. Only the still mathematically retarded use degrees.
    If you would like a reply, use a number, i.e. radians.
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    Re: Radian question with integral

    Quote Originally Posted by Plato View Post
    Give up the use of degrees. Only the still mathematically retarded use degrees.
    If you would like a reply, use a number, i.e. radians.
    I dont know if I should take that as an insult or constructive criticism, but I used radians and got a decimal and it said it was wrong I guess. It doesn't specify which to use as well.

    3arcsin(pi/3)-3arcin(pi/6)
    and I got 90 as an answer
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    Re: Radian question with integral

    Quote Originally Posted by Steelers72 View Post
    I dont know if I should take that as an insult or constructive criticism, but I used radians and got a decimal and it said it was wrong I guess. It doesn't specify which to use as well.
    3arcsin(pi/3)-3arcin(pi/6)
    and I got 90 as an answer
    "as an insult or constructive criticism" that was meant as neither.
    It states a fact. Most modern mathematics in fact does not use degrees.

    You clearly are confused. \arcsin\left(\frac{\pi}{3}\right) is not even defined. In order for \arcsin(t) to be defined, you must have -1\le t\le 1. and then \frac{-\pi}{2}\le\arcsin(t)\le\frac{\pi}{2}.
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    Re: Radian question with integral

    The answer was 90 but in radians is pi/2. Thanks!
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