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    Attachment 616444
    Hi, please can someone help me with this maths question?

    I've attached what to next but i'm stuck where to go next so any advice would be appreciated.

    Thanks,
    Amelia
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    (Original post by acantwellhyde)
    Hi, please can someone help me with this maths question?

    I've attached what to next but i'm stuck where to go next so any advice would be appreciated.

    Thanks,
    Amelia
    there is no attachment, try posting it again
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    I've added it now Name:  IMG_0659.jpg
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    (Original post by DylanJ42)
    there is no attachment, try posting it again
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    (Original post by acantwellhyde)
    I've added it now
    (1+\sin(x))^2 \equiv 1+2\sin(x)+\sin^2(x)\not \equiv 2+2\sin(x)+\sin^2(x)
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    Thank you for your help but I don't really understand what you have done to get this answer. I don't really want the answer I just want someone to help me with the next few steps please..
    (Original post by RDKGames)
    (1+\sin(x))^2 \equiv 1+2\sin(x)+\sin^2(x)\not \equiv 2+2\sin(x)+\sin^2(x)
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    (Original post by acantwellhyde)
    I've added it now Name:  IMG_0659.jpg
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     \displaystyle \frac{(1 + \sin x)(1 + \sin x) + (\cos x)(\cos x)}{(\cos x)(1+ \sin x)}

    start again from here, remember for the bracket on the top line to use F.O.I.L to multiply it out.

    In your working you have implied that 1 x 1 = 2.

    also  \displaystyle (\cos x)^2 is usually written as  \displaystyle \cos ^2 x and not  \displaystyle \cos x^2 , likewise for sine.

    Finally what identities do you know involving  \displaystyle \cos ^2x and  \displaystyle \sin ^2x ?
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    (Original post by acantwellhyde)
    Thank you for your help but I don't really understand what you have done to get this answer. I don't really want the answer I just want someone to help me with the next few steps please..
    You have (1+\sin(x))(1+\sin(x)) on the second line of the LHS working which is the same as (1+\sin(x))^2 and what I'm saying is that you've expanded it wrong. The constant should be a 1, not a 2.
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    Thank you so much! I'll have another go and post my answer shortly
    (Original post by DylanJ42)
     \displaystyle \frac{(1 + \sin x)(1 + \sin x) + (\cos x)(\cos x)}{(\cos x)(1+ \sin x)}

    start again from here, remember for the bracket on the top line to use F.O.I.L to multiply it out.

    In your working you have implied that 1 x 1 = 2.

    also  \displaystyle (\cos x)^2 is usually written as  \displaystyle \cos ^2 x and not  \displaystyle \cos x^2 , likewise for sine.

    Finally what identities do you know involving  \displaystyle \cos ^2x and  \displaystyle \sin ^2x ?
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    Got it! Thanks for your help. This is correct, right?Name:  IMG_0661.jpg
Views: 32
Size:  492.1 KB
    (Original post by acantwellhyde)
    Thank you so much! I'll have another go and post my answer shortly
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    (Original post by acantwellhyde)
    Got it! Thanks for your help. This is correct, right?Name:  IMG_0661.jpg
Views: 32
Size:  492.1 KB
    perfect, well done
 
 
 
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