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Thread: Can someone please help with q22, 23 and 24

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    Can someone please help with q22, 23 and 24


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    Re: Can someone please help with q22, 23 and 24

    22)



    Find the area of the sector and subtract it from the area of the triangle .
    __________________________________________________ _______________________________________

    23)

    a) The arc is equal to the circumference of the cone's base. With that information you can calculate the radius.

    b) Once you know the slanted height of the cone and its base's radius, you can form a triangle to calculate the perpendicular height.

    c) Use the volume formula for a cone.

    d) The curved surface area is equal to the area of the sector .
    __________________________________________________ _______________________________________

    24)



    a) First calculate the area of the sector in terms of and . Then express in terms of by using the perimeter and the arc length formula.

    b) Differentiate the area formula and identify its maximum value. The domain should be , but it might not matter either way.
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    Re: Can someone please help with q22, 23 and 24

    How is the solution 4/3 (4pi -3 root 3) i got 4/3(2 Pi - 3 root 3)

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    Re: Can someone please help with q22, 23 and 24

    Quote Originally Posted by kpad5991 View Post
    How is the solution 4/3 (4pi -3 root 3) i got 4/3(2 Pi - 3 root 3)
    Gonna need a bit more information.... what question?
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    Re: Can someone please help with q22, 23 and 24

    Quote Originally Posted by fan96 View Post
    Gonna need a bit more information.... what question?
    Sorry q22

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    Re: Can someone please help with q22, 23 and 24

    Quote Originally Posted by fan96 View Post
    22)



    Find the area of the sector and subtract it from the area of the triangle .
    __________________________________________________ _______________________________________

    23)

    a) The arc is equal to the circumference of the cone's base. With that information you can calculate the radius.

    b) Once you know the slanted height of the cone and its base's radius, you can form a triangle to calculate the perpendicular height.

    c) Use the volume formula for a cone.

    d) The curved surface area is equal to the area of the sector .
    __________________________________________________ _______________________________________

    24)



    a) First calculate the area of the sector in terms of and . Then express in terms of by using the perimeter and the arc length formula.

    b) Differentiate the area formula and identify its maximum value. The domain should be , but it might not matter either way.
    Q22

    OA = OB = 4cm
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    Re: Can someone please help with q22, 23 and 24

    I just realised I made a mistake with that diagram. The radius should be 4cm, not 2cm.



    Area of sector





    Area of triangle





    Area of shaded segment



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