Recent content by e179285

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    How many additive cosets exist for the ideal I in the subring R?

    Let R be the subring {x + yi : x, y in 2Z} of C, and let I be the ideal {x + yi : x,y in 2Z}of R. How many additive cosets has I in R? List them clearly. I know definition of ideal but ı don't know how to write in set is that question describe.Please help :)
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    What Is the Sum of the Series Ʃ n/(n+1)! from n=1 to Infinity?

    ı know ratio test and ı found it is convergent but the question wants finding sum of the series I don't know how to do this
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    What Is the Sum of the Series Ʃ n/(n+1)! from n=1 to Infinity?

    Hi sharks, what ı can use ratio test for ?
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    Approximation Using Taylor POlynomial

    Find an approximate value of the number e-0.1 with an error less than 10-3 ı know that ex = Ʃ(from zero to ınfinity) xn / n!=1+x/1!+x 2/2!+... ı don't know how to use e-0.1 in this question.Do ı write -0.1 instead of x in ex series?
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    What Is the Sum of the Series Ʃ n/(n+1)! from n=1 to Infinity?

    Ʃ (from n=1 to ınfınıty ) n /(n+1)! the questions asks sum of the this series. I try to write this series as Ʃ 1/(n-1)!.(n+1)but ı couldn't simulate any series. How can ı do this ?
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    Is A3 a Normal Subgroup of S3?

    H=A3= {(1),(1 2 3),(1 3 2)} and G=S3 ={ (1),(1 2 3),(1 3 2),(1 2 ),(1 3),(1 2 3) } Is H is normal subgroup of G ? I try g=(1 2 3 ) for gH=Hg but gH≠Hg for all g ε G.In this situation,H is normal subgroup pf G?
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    All Subgroups of S3: Lagrange's Theorem Explained

    The question wants all subgroups of S3 . If H≤S 3 , then ; IHI=1,2,3,6 by Lagrance's Theorem. In other words, order of H can be 1,2,3 and 6. What ı want to ask is how to write subgroup of S3. For example,is H 1 (1) ?
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    Determine this sequence increasing or decreasing

    A sequence (an) is recursively defined by a1 = 1 and an+1 =1 /(2+an ) for all n≥1 I'll prove this sequence is convergent by monoton sequence theorem.ı can find ıt is bounded but ı cannot decide it is monoton because when ı write its terms,Its terms are increasing sometimes decreasing...
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    Determine Convergent or Divergent

    an = [cos (3n) )] /n.cos(1/n) My solution is , I wrote an as liman→∞ [cos (3n) )] /[ cos(1/n) / (1/n) ) . We get liman→∞ cos(3n) / ( 1/0 ) . I think solution of this limit is zero but ı'm not sure cos(3n) .I think cos(3n) as a number and number/infinity is zero .As a result of...
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    Arc Length and Surface question about hyperbolic function

    I'm sorry,ı made a mistake by writing value.It will be 2sinh(a),but ı don't understand why it is not equal to 2a+4
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    Arc Length and Surface question about hyperbolic function

    If the circumference of the region bounded by the curve y=cosh(x) and the lines y=0 x=a and x=-a is 2a+4, where a>0 find the area of the surface obtained by rotating the part of the curve y=cosh(x) between x=a x=-a and around the x axis. This is my homework question.I tried to solve it.I...
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    Increasing or Decreasing Sequence

    My sequence is the second one.If it is neither increasing or decreasing ,how will ı show that it is convergent sequence? ı think there is a problem about sequence. Thank you for efforts :)
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    Increasing or Decreasing Sequence

    a1=1/3,a2=7/21,a3=3/7,a4=7/17,a5=17/41 ... according to my calculation, a1>a2, a3>a2, a5>a4, a3>a4 How can ı decide?
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