We'll write the definite integral of the
function:
Int x^ndx/(x^n+1)(x=0 to x=2) = Intx^ndx/(x^n+1)(x=0 to
x=1) + Int x^ndx/(x^n+1)(x=1 to x=2)
Since n is natural,
then:
x^n < x^n + 1
x^n/(x^n +
1) < 1
We'll integrate both
sides:
Int x^ndx/(x^n + 1) < Int
dx
Also, Int x^ndx/(x^n + 1) < Int x^n
dx
Intx^ndx/(x^n+1)(x=0 to x=1) + Int x^ndx/(x^n+1)(x=1 to x=2)
< Int x^n dx(x=0 to x=1) + Int dx(x=1 to x=2)
Int x^n dx(x=0
to x=1) = x^(n+1)/(n+1) = 1/(n+1) - 0/(n+1)
Int x^ndx =
1/(n+1)
Int dx(x=1 to x=2) = x = 2 - 1 =
1
Therefore I = Int x^ndx/(x^n + 1) < 1/(n+1) +
1.
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