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    So my friend gave me this problem:
    2^a + 3^b = c^2 where a, b and c are all integers. I have got one solution where a=4, b= 2 and c=5 but I cant find any others. If this is the only solution I also have to prove why but have no idea how to do this.
    Any help would be great
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    TeeEm ("Miss" :P )
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    (Original post by Quantum42)
    So my friend gave me this problem:
    2^a + 3^b = c^2 where a, b and c are all integers. I have got one solution where a=4, b= 2 and c=5 but I cant find any others. If this is the only solution I also have to prove why but have no idea how to do this.
    Any help would be great
    Remember that c is squared, so you really mean c = \pm 5.

    Also, what about a=0, b=1, c = \pm 2? Or a=3, b=0, c= \pm 3?
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    (Original post by FrenchUnicorn)
    TeeEm ("Miss" :P )
    sorry but I am teaching
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    (Original post by TeeEm)
    sorry but I am teaching
    PRSOM *so frustrating*
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    (Original post by Quantum42)
    So my friend gave me this problem:
    2^a + 3^b = c^2 where a, b and c are all integers. I have got one solution where a=4, b= 2 and c=5 but I cant find any others. If this is the only solution I also have to prove why but have no idea how to do this.
    Any help would be great
    Some initial considerations, you want 2^a + 3^b to be a square number. You also know that 2 and 3 are primes.
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    (Original post by Zacken)
    Some initial considerations, you want 2^a + 3^b to be a square number. You also know that 2 and 3 are primes.
    Sorry still really confused as to how that helps
 
 
 
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