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Show that cos(x)=x has a root on R.?
Show that cos(x)=x has a root on R.
1 AnswerMathematics8 years agoLet f,g be continuous from R to R, and suppose that f(r)=g(r) for all rational numbers r. Is it true that f(x?
Let f,g be continuous from R to R, and suppose that f(r)=g(r) for all rational numbers r. Is it true that f(x)=g(x) for all x in R?
2 AnswersMathematics8 years agoprove that the series sum(((-1)^n)/sqrt(n), n=1..infinity) converges?
Using the alternating harmonic series, show that the series sum(((-1)^n)/sqrt(n), n=1..infinity) converges.
1 AnswerMathematics9 years agoLet x_n:= 1/ln(n+1) for n in N.?
a) use the definition of limit to show that lim(x_n)=0.
b) Find a specific value of K(epsilon) as required in the definition of limit for each of i) epsilon=1/2, and ii) epsilon=1/10
1 AnswerMathematics9 years agoIf I_n is a nested sequence of intervals and if I_n=[an,bn]?
If I_n is a nested sequence of intervals and if I_n=[an,bn], show that a1 <=a2<=...<=an<=... and b1>=b2>=...>=bn>=...
1 AnswerMathematics9 years agoLet S be a nonempty subset of R that is bounded below. Prove that inf(S)= -sup{-s: s in S}?
Let S be a nonempty subset of R that is bounded below. Prove that inf(S)= -sup{-s: s in S}
2 AnswersMathematics9 years agoProve that there does not exist r in Q such that r^2=3?
1 AnswerMathematics9 years agoIf a>0, b>0 and n in N, prove that a<b if and only if a^n<b^n?
2 AnswersMathematics9 years agoProve that n^3+5 is divisible by 6 for all n in N.?
3 AnswersMathematics9 years agoDetermine and sketch the set of pairs (x,y) in RxR that satisfy abs(x)+abs(y)=1?
Also, if you can, Determine and sketch the set of pairs (x,y) in RxR that satisfy abs(x*y)=2.
1 AnswerMathematics9 years agoLet K := {s + t√2:s,t ∈ Q}. Show that K satisfies the following: If x1,x2 ∈ K, then x1+x2 ∈ K and x1x2 ∈ K. If?
Let K := {s + t√2:s,t ∈ Q}. Show that K satisfies the following:
a) If x1,x2 ∈ K, then x1+x2 ∈ K and x1x2 ∈ K.
b) If x not=0 and x in K, then 1/x in K
1 AnswerMathematics9 years agoProve that if a,b are real numbers, then -(a/b)=(-a)/b if b not=0?
Specify the field axiom at each step
2 AnswersMathematics9 years agoProve that 1^2-2^2+3^2+...+(-1)^(n+1)*n^2=(-1)^(n+1)*n*(n+1)/2 for all n in N?
Prove that 1^2-2^2+3^2+...+(-1)^(n+1)*n^2=(-1)^(n+1)*n*(n+1)/2 for all n in N. (By induction)
1 AnswerMathematics9 years agoFor the following functions, state which have uniformly convergent Fourier series and which do not.?
Briefly explain why.
a) f(x)=x^2 on [-3,3), period 6.
b) f(x)=cos(x) on [-Pi/3, Pi/3), period 2*Pi/3
c) f(x)=x^3 on [-1,1), period 2.
d) f(x)=abs(x)-x on [-2,2), on period 4.
e) f(x)=sin(e^(abs(x)) on [-1,1), period 2.
1 AnswerMathematics9 years agoprove the following orthogonality theorem for the set of functions {sin(n*Pi*x/a)} n=1..infinity over the inte?
prove the following orthogonality theorem for the set of functions {sin(n*Pi*x/a)} n=1..infinity ov erthe interval [0,a]: For m not equal to n, int(sin(n*Pi*x/a)sin(m*Pi*x/a), x=0..a)=0 and int(sin^2(n*Pi*x/a), x=0..a)=a/2
1 AnswerMathematics9 years agoProve 3^n=Sum where 0<=i+j<=n of n!/i!*j!*(n-i-j)!?
1 AnswerMathematics9 years agoRefer to the sequence S where S_n denotes teh number of n-bit strings that do not contain the pattern 00.?
1. Find a recurrence relation and initial conditions for the sequence {S_n}.
2. Show that S_n=f_n+1, n=1, 2,... where f denotes the Fibonacci sequence.
1 AnswerMathematics9 years agoLet S_n,k denote the number of ways to partition an n-element set into exactly k nonempty subsets.?
The order of the subsets is not taken into account.
a) Show that S_n,k=0 if k>n
b) Show that S_n,n=1 for all n>=1
c) Show that S_n,1=1 for all n>=1
d)Show that S_3,2=3
e) Show that S_4,2=7
f) Show that S_4,3=6
g) Show that S_n,2=2^(n-1)-1 for all n>=2
h) Show that S_n,n-1=C(n,2) for all n>=2
i) Find a formula for S_n,n-2, n>=3, and prove it.
I know this is extremely long. Best answer will be awarded.
1 AnswerMathematics9 years ago