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    "Let ABCD be a rectangle and CE an arc of the circle centred at A. If DA =4cm and AC = 8cm then what is the area of the shaded sector of the circle.
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    (Original post by cotton candie)
    "Let ABCD be a rectangle and CE an arc of the circle centred at A. If DA =4cm and AC = 8cm then what is the area of the shaded sector of the circle.
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    it is not clear where E is.... the shaded part of your diagram does not look like a sector.
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    yes I agree we need the location of E to go ahead
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    Name:  tsrdiagram.png
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    the bit sticking out of the right of the rectangle looks like a segment, but the centre of the circle would be the middle of the rectangle, not A.
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    I've made the required changes.... can someone please help me solve this problem now.
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    (Original post by cotton candie)
    I've made the required changes.... can someone please help me solve this problem now.
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    could you use the formula 1/2* r squared * theta where r is AC and theta is angleCAB?
    you already know CA and AD, AD = BC , you can use trig to work out angleCAB
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    don't u want the region BCE?
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    AC= 8
    BC=4
    sin-1(4/8) = 30
    angleCAB= 30
    Area of sector = 1/2 * 8squared * pi/6 ( theta must be in radians)
    area = 16/3 pi
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    (Original post by Brudor2000)
    AC= 8
    BC=4
    sin-1(4/8) = 30
    angleCAB= 30
    Area of sector = 1/2 * 8squared * pi/6 ( theta must be in radians)
    area = 16/3 pi
    Thank u
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    (Original post by Brudor2000)
    AC= 8
    BC=4
    sin-1(4/8) = 30
    angleCAB= 30
    Area of sector = 1/2 * 8squared * pi/6 ( theta must be in radians)
    area = 16/3 pi
    30/360 * pi * 8^2 = 16/3pi
    Posted on the TSR App. Download from Apple or Google Play
 
 
 
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