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p1-rads, trig etc [mix] watch

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    See attachment for qu. Needing help with c.
    if theta.r^2/2=area of sector, well this divided by r^2sinthetacostheta does not give what they want!
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    (Original post by BossLady)
    See attachment for qu. Needing help with c.
    if theta.r^2/2=area of sector, well this divided by r^2sinthetacostheta does not give what they want!
    Is it not just basic application of the cosine rule?
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    (Original post by Bhaal85)
    Is it not just basic application of the cosine rule?
    :confused: not a.......for c....
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    (Original post by BossLady)
    :confused: not a.......for c....
    You have as a result from a)

    2ø - 3sinø = 0
    ø = (3/2)sinø
    ========

    A1 = Area triangle = r²sinøcosø
    A2 = Area sector = ½r²(2ø)

    A2/A1 = r²ø/(r²sinøcosø)
    A2/A1 = r²(3/2)sinø/(r²sinøcosø), using ø = (3/2)sinø

    cancelling out gives,

    A2/A1 = (3/2)/(cosø)
    A2/A1 = 3/(2cosø)
    ============
 
 
 
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