for how many integers n is 2^n= n^2 ?
It helps to know that the function 2^x is more expansive than x^2 for large positive x and converges quickly to 0 for negative x.
So we know we only have to check small values of x. For positive x, it is easy to see this is true for x=2,4 and then the function 2^x explodes
For negative x, 2^-1 is less than -1^2 already so no negative integers can satisfy the equalityAnswer is (c) or 2
1) Algebra-101 2) Sequences 3) Set combinatorics 4) 3-D geometry
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