$f(x) = 2^\alpha x^2+2^\beta x - 2^\gamma=y^2$

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A few questions regarding a polynomial of degree 2:

$f(x) = ax^2 + bx - c$

where $a,b,c$ are given positive powers of 2.

Or more explicitly:

$f(x) = 2^\alpha x^2+2^\beta x - 2^\gamma$

where $\alpha,\beta,\gamma$ are positive integers

1) Can one theoretically (I mean not by an algorithm which include any trial and error parts) determine if there is a positive integer value $x_0$ such that $f(x_0)$ is a square (namely that there is a positive integer $y$ such that $f(x_0)=y^2$) depending on the values of $a,b,c$?

2) Can one generate all solutions given one solution?

3) Given there is a solution, is there an algorithm to yield the solution?

Thanks

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If so we can write $$2^{\alpha}x^2+2^{\beta}x-2^{\gamma}=(Ax+B)^2$$ so we get $$2^{\alpha}=A^2$$ $$2AB=2^{\beta}$$ $$-2^{\gamma}=B^2$$ The last equation isn't fulfilled for any real number $$\gamma,B$$