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    (Original post by dfbenjamin)
    For that I got (x+a/2)^2 + (y+b/2)^ = c + (a+b)/4

    This is a circle with radius (c + (a+b)/4)^(1/2), centre (-a/2, -b/2)

    So the origin is ((a/2)^2 + (b/2)^2)^(1/2) away from the centre

    so c + a/4 + b/4 > a^2/4 + b^2/4
    so 4c > a^2 + b^2 + a + b

    what have I done wrong here?
    Ya I got the answer with 4c in it.
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    (Original post by AmanGottu)
    Ya I got the answer with 4c in it.
    yeah but the answer with 4c was just 4c>a^2 + b^2

    it didn't have the a + b as well
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    (Original post by dfbenjamin)
    For that I got (x+a/2)^2 + (y+b/2)^ = c + (a+b)/4

    This is a circle with radius (c + (a+b)/4)^(1/2), centre (-a/2, -b/2)

    So the origin is ((a/2)^2 + (b/2)^2)^(1/2) away from the centre

    so c + a/4 + b/4 > a^2/4 + b^2/4
    so 4c > a^2 + b^2 + a + b

    what have I done wrong here?
    on the very first line when you complete the square it should be c+(a^2+b^2)/4
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    I got c>0 (or was it c<0? the inequality with only c in).
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    (Original post by dfbenjamin)
    yeah but the answer with 4c was just 4c>a^2 + b^2

    it didn't have the a + b as well
    I just remember when working the problem, it made sense and I was pretty sure that was right... Do you know what the right answer is?
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    (Original post by dfbenjamin)
    For that I got (x+a/2)^2 + (y+b/2)^ = c + (a+b)/4

    This is a circle with radius (c + (a+b)/4)^(1/2), centre (-a/2, -b/2)

    So the origin is ((a/2)^2 + (b/2)^2)^(1/2) away from the centre

    so c + a/4 + b/4 > a^2/4 + b^2/4
    so 4c > a^2 + b^2 + a + b

    what have I done wrong here?
    First line: should be (x+a/2)^2 + (y+b/2)^ = c + (a^2+b^2)/4
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    (Original post by dfbenjamin)
    A^n(B^m(x))= (2^n)(3^n)x+(2^n*3^n - 1)

    I never found this - would you mind explaining how it is derived?
    This is just concerning the compound functions used in the last part - I don't know how this remains the same when the order of the As and Bs is muddled with, so I brute forced the 2nd last part to give the same result.Name:  IMG_20161103_185528.jpg
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    (Original post by m0.4444)
    on the very first line when you complete the square it should be c+(a^2+b^2)/4
    oh yeah of course forgot that (a/2)^2 = a^2/4

    thanks!

    and then everything cancels out (just noticed another mistake in the answer i posted here lol but I didn't make that mistake in the exam)
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    (Original post by dfbenjamin)
    oh yeah of course forgot that (a/2)^2 = a^2/4

    thanks!

    and then everything cancels out (just noticed another mistake in the answer i posted here lol but I didn't make that mistake in the exam)
    Do you guys remember what the answer choices were for that question? Was there anything that said c could be anything? (I'm trying to think if I made a mistake by putting that answer choice or put c>0)
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    (Original post by pressurize)
    Do you guys remember what the answer choices were for that question? Was there anything that said c could be anything? (I'm trying to think if I made a mistake by putting that answer choice or put c>0)
    I know there was c>0, 4c>a^2 + b^2 and 4c<a^2 + b^2

    not sure about what the other one was though
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    So was anyone able to get the explanation for the second last part of Q2, or the anything in the last part of Q2?
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    (Original post by pressurize)
    Do you guys remember what the answer choices were for that question? Was there anything that said c could be anything? (I'm trying to think if I made a mistake by putting that answer choice or put c>0)
    I immediately recognized c>0 but now im thinking i put c<0
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    (Original post by m0.4444)
    I immediately recognized c>0 but now im thinking i put c<0
    I thought there was just one inequality only with c?
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    Uggh now I think that I put c can be anything. Was that even an answer choice?
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    For Q5, if your reasoning is right and you wrote it down and you get the first half right but then you make a silly algebra mistake and get to an incorrect answer would you still get like method marks or something for the working/reasoning?
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    (Original post by pressurize)
    Uggh now I think that I put c can be anything. Was that even an answer choice?
    I'm almost certain they were all inequalities so I wouldn't worry
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    (Original post by RuairiMorrissey)
    I thought there was just one inequality only with c?
    Thats good then.
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    For b did anyone put 2 + sqrt2.
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    (Original post by dfbenjamin)
    I'm almost certain they were all inequalities so I wouldn't worry
    But how many inequalities where there with c and 0.
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    (Original post by 11234)
    For b did anyone put 2 + sqrt2.
    i got that one wrong. But i think its 2 - sqrt2
 
 
 
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