Soru
1. Let f(x)=sin(x) and apply Theorem 4.1. (a) Use x_(0)=0 and find P_(5)(x),P_(7)(x) and P_(9)(x) (b) Show that if vert xvert leqslant 1 , then the approximation sin(x)approx x-(x^3)/(3!)+(x^5)/(5!)-(x^7)/(7!)+(x^9)/(9!) has the error bound vert E_(9)(x)vert lt 1/10!leqslant 2.75574times 10^-7 (c) Use x_(0)^ast =pi /4 and find P_(5)(x) , which involves powers of (x-pi /4)
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Profesyonel · 6 yıl öğretmeni
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(a) To find
,
, and
, we can use the Taylor polynomial approximation formula:
For
, we have
,
,
, and so on.
(b) To show that if
, then the approximation
has the error bound
, we can use the error bound formula for Taylor polynomials:
where
is the maximum value of
on
.In this case,
,
, and
. The maximum value of
on
is
, so we have:
Since
, we have
, so
.(c) To find
when
, we can use the same Taylor polynomial approximation formula as in part (a), but with
:$P_{5}(x) = \sin(\pi/4) + \cos(\pi/4)(x - \pi/4) + \frac