My answer: Fuck this just give me a rifle and point me towards the enemy lines!

  • TraschcanOfIdeology [they/them, comrade/them]@hexbear.net
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    7 months ago

    And the numerator on the left can be multiplied by 2/2

    I don’t understand this step. Why did you multiply is for 2/2, I don’t see how it simplifies the numerator on the left, when expanding the fraction sum leads to 4a(b+c)^2n-1, something simpler to factor using x2-y2=(x+y) (x-y)

    • Achyu@lemmy.sdf.org
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      7 months ago

      (2a2 (b+c)2n - 1/2) x 2/2 = (4a2 (b+c)2n - 1) x 1/2
      Let’s keep the 1/2 aside for now.

      We can write 4a2 (b+c)2n as 22 a2 ((b+c)n )2 and 1 as 12

      So (4a2 (b+c)2n - 1) = ( 2a(b+c)n )2 - 12

      Comparing with x2 - y2 we have x = 2a(b+c)n and y = 1
      With with x2 - y2 =(x+y) (x-y), we get:

      (2a(b+c)n)2 - 12 = (2a(b+c)n + 1) (2a(b+c)n - 1)

      We can then cancel the common (2a(b+c)n - 1) term from the numerators on both sides…

      with the assumption that 2a(b+c)n - 1 ≠ 0. If it’s zero, then we introduce the issue of 0 x something = 0 x something.
      0 x 1 = 0 x 2 = 0
      We can’t cancel the common zero and say that 1 = 2. So 0/0 or 1/0 is an issue, but with the assumption that it isn’t 0, we can cancel it out.

      I multiplied and dividing by 2 because in effect it changes nothing to the result as 2/2 = 1. But it helps to rearrange and simplify stuff.