True or false:
is a transcendental number but is not transcendental.
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I will here prove that e is transcendental:
I'll start from the formula achieved from integration by parts:
∫ 0 r e − x f ( x ) d x = − [ e − x f ( x ) ] 0 r + ∫ 0 r e − x f ′ ( x ) d x .
If f ( x ) is a polynomial of x N th degree, we get:
F ( x ) = f ( x ) + f ′ ( x ) + f ′ ′ ( x ) + . . . + f N ( x )
∫ 0 r e − x f ( x ) d x = F ( 0 ) − F ( r ) e − r
From which:
F ( r ) = F ( 0 ) e r − e r ∫ 0 r e − x f ( x )
Let's now suppose that e satisfies an algebraic equation: a 0 e n + a 1 e n − 1 + . . . + a n − 1 e + a n = 0 ,
and let's define for f ( x ) : f ( x ) = ( p − 1 ) ! 1 x p − 1 ( 1 − x ) p ( 2 − x ) p . . . ( n − x ) p .
So the equation: F ( r ) = F ( 0 ) e r − e r ∫ 0 r e − x f ( x ) implies, that if r = n , so r = n − 1 , r = n − 2 , . . . r = 0 there are totally n + 1 equations, which we multiply by a 0 , a 1 , a 2 , . . . , a n and sum together.
If we then substitute the F ( 0 ) on the right hand, we get:
a 0 F ( n ) + a 1 F ( n − 1 ) + . . . + a n − 1 F ( 1 ) + a n F ( 0 ) = − k = 0 ∑ n a k e n − k ∫ 0 n − k e − x f ( x ) d x .
Which is impossible for e , as:
If we plug in f ( x ) any of the numbers 1 , 2 , . . . , n we get either 0 or an integer divisible by p . So for x = 0 , we get f ( 0 ) = f ′ ( 0 ) = f ′ ′ ( 0 ) = . . . f ( p − 2 ) ( 0 ) = 0 ;
Further f ( p − 1 ) ( 0 ) = ( 1 × 2 × 3 . . . × n ) p ; f ( p ) ( 0 ) ; f ( p + 1 ) ( 0 ) are integers, which again are divisible by p . So if p is a prime number p > n ,
F ( 0 ) = n ∈ Z not divisible by p .
Let also p > ∣ a n ∣ , then the polynomial:
a 0 F ( n ) + a 1 F ( n − 1 ) + . . . + a n − 1 F ( 1 ) + a n F ( 0 )
is a whole number not divisible by p .
From − k = 0 ∑ n a k e n − k ∫ 0 n − k e − x f ( x ) d x we assume from the Intermediate value theorem, that:
∣ ∫ 0 n − k f ( x ) e − x d x ∣ = ∣ f ( ξ ) ∣ ( 1 − e − n + k ) < ∣ f ( ξ ) ∣ < ( p − 1 ) ! n ( n + 1 ) p − 1 .
So let
M = ∣ a 0 ∣ e n + ∣ a 1 ∣ e n − 1 + ∣ a 2 ∣ e n − 2 + . . . + ∣ a n ∣ , then
− k = 0 ∑ n a k e n − k ∫ 0 n − k e − x f ( x ) d x < M ( p − 1 ) ! n ( n + 1 ) p − 1 in absolute value.
However the prime number p is defined only by conditions p > ∣ a n ∣ , p > n , so it can be of any size. So if they are large enough, the expression: M ( p − 1 ) ! n ( n + 1 ) p − 1 becomes arbitrarily small, for example we could choose a p large enough, so that the expression is smaller than 1 , then the equation
∣ a 0 F ( n ) + a 1 F ( n − 1 ) + . . . + a n − 1 F ( 1 ) + a n F ( 0 ) = − k = 0 ∑ n a k e n − k ∫ 0 n − k e − x f ( x ) d x ∣ must equal at least 1 in it's absolute value equal to a number < 1 , which is impossible since an absolute value can't be negative. That means that e doesn't satisfy the equation a 0 e n + a 1 e n − 1 + . . . + a n − 1 e + a n = 0 , which means, that e is transcendental .
Therefore the answer to the claiming is false