35 items are filed under this topic.
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A mathematical expression with the answer 7 |
2012-11-10 |
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From emily:
hey um i need to find and problem that fallows bedmas that has one division one multiplication and one sub and one add and one brackets and one exponents that has the answer of number 7
Answered by Penny Nom. |
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Sales as a function of advertising |
2010-12-08 |
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From Adori:
The sales S(in thousands if units) of a product after x hundred dollars is spent on advertising is given by S=10(1-e^kx). Find S as a function of x if 2500 units are sold when $500 is spent on advertising.
Answered by Penny Nom. |
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I need to learn to think mathematically |
2010-07-20 |
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From Student:
I need to learn to think mathematically, and like math while doing it, got any ideas, help.
Answered by Walter Whiteley. |
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Fibonacci and induction |
2010-07-12 |
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From James:
I'm trying to prove by induction that F(n) <= 2^(n-1)
where f(1)=f(2)=1 and f(k)=f(k-1)+f(k-2) for k >=3 is the Fibonacci sequence
Answered by Stephen La Rocque and Tyler Wood. |
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A proof by induction |
2010-03-25 |
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From SAMUEL:
use mathematical induction to proof that each statement is true for every positve integer n
1/1.2+1/2.3+1/3.4+......1/n(n+1)=n/n+1
Answered by Robert Dawson. |
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The nth derivative of x^(n-1) log x |
2010-03-10 |
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From shambodeb:
This is a successive differentiation problem by Leibnitz theorem
If y = xn-1 log x ; Proof nth derivative y(n) = (n-1)!/x
Answered by Harley Weston. |
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A proof by induction |
2010-01-12 |
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From Bhavya:
Prove by induction that if Xi >= 0 for all i, then
(Summation Xi from 1 to n)^2 >= Summation Xi^2 from 1 to n
Answered by Penny Nom. |
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Show your work |
2009-09-02 |
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From Gerald:
We have a 6th grade student who can solve math problem successfully without showing her work. The teacher thinks it is not fair that she doesn't show her work and the other have to and do. What sort of classroom accommodation(s) would you recommend for this type of student. It would seem to be a popular problem since there are many student who think more global than sequential.
Answered by Victoria West, Penny Nom and Robert Dawson. |
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Math in everyday life |
2009-08-03 |
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From Naveen:
Dear sir,
We are advised to do a project on "Mathematical modeling to solve various problems
of our everyday life/environmental related problems...... Can u plz help us by mailng some
ideas, suggestion,reference to make my project successful.... Thanking you......
Waiting for your favourable reply......
Answered by Penny Nom. |
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Mathematical induction |
2008-09-05 |
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From James:
I need to prove a problem by induction regarding the Triangle Inequality. The problem is
abs(a1 + a2 +...+an) <= abs(a1) + abs(a2) +...+ abs(an).
Answered by Victoria West. |
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Mathematical induction |
2008-07-11 |
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From lyn:
can you give me a basic example of a mathematical induction
Answered by Harley Weston. |
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The sum of the digits of a number |
2008-06-23 |
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From Ben:
Question: Using mathematical induction, prove that if the sum of the digits of a number is divisible by three, then the number itself is also divisible by 3.
Answered by Penny Nom. |
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1/(1x2)+1/(2x3)+1/(3x4)...+1/(n(n+1)) |
2008-02-20 |
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From hossun:
Find a formula for 1/(1x2)+1/(2x3)+1/(3x4)...+1/(n(n+1))
by examining the values of this expression for small values of n.
Use mathematical induction to prove your result.
Answered by Stephen La Rocque. |
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The Principle of Mathematical Induction |
2007-12-15 |
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From iris:
we have some confusion in our problem. Please help us.
We would like to know "the principle of mathematical induction"
(i) for n=1, p(1) is true.
(ii) assume that for n=k>=1, p(k) is true we have to prove p(k+1) is true. Here (Is n=k>=1 true? or Is n=k.1 true?)
Thanks.
Answered by Penny Nom and Victoria West. |
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Principia Mathematica |
2007-04-12 |
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From victoria:
i need help making a poster on emilie du chatelet a great mathematician can you describe
the newton principia because i know that she worked on it
thanks,
victoria
Answered by Stephen La Rocque and Penny Nom. |
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The proof of inequality by mathematical induction |
2006-12-07 |
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From Carol:
S(n) = 2^n > 10n+7 and n>=10
Answered by Stephen La Rocque. |
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The Fibonacci sequence |
2006-11-21 |
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From Ross:
Let f0 = 0; f1 = 1,... be the Fibonacci sequence where for all n greater than or equal to 2 fn = fn-1 + fn-2. Let Q = (1+square root of 5)/2. Show that for all positive n greater than or equal to 0, fn less than or equal to Q^(n-1).
Answered by Penny Nom. |
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Composition of functions |
2006-11-19 |
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From RJ:
Let f0(x) = 2/2-x and fn+1 = f0 o fn for n greater than or equal to 0. Find a formula for fn and prove it by mathematical induction. Recall that o represents function composition. i.e., (f o g)(x) = f(g(x)).
Answered by Stephen La Rocque. |
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Induction |
2006-11-16 |
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From John:
Find a formula for
1/(1x3)+1/(2x4)+1/(3x5)...+1/(n(n+2))
by examining the values of this expression for small values of n. Use mathematical induction to prove your result.
Answered by Penny Nom. |
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A proof by induction |
2006-11-06 |
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From Zamira:
i have a problem with this mathematical induction: (1^5)+(2^5)+(3^5)+...+(n^5) = ((n^2)*((n+1)^2)*((2n^2)+2n-1))/12
Answered by Penny Nom. |
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A triangle problem |
2006-05-18 |
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From Jim:
Right angle triangle with a hypotenuse of 20 units.
Square inside the triangle with sides of 4 units, the square shares two sides with both legs of the triangle, and the corner touches the hypotenuse limiting the triangles size.
Answered by Penny Nom. |
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Modelling monthly temperature with a cosine |
2004-12-25 |
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From Regis:
The average monthly temperature for a location in Ontario as a function of month number can be modelled using the equation y = a cos[k(t + b)] + d.
Answered by Harley Weston. |
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Proof by induction |
2004-11-20 |
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From Vic:
Problem: Find the first 4 terms and the nth term of the infinite sequence defined recursively as follows:
a(1) = 3 and a(k+1) = 2a(k) for k -> 1.
Note: Quantities in brackets are subscripts
-> means 'equal to or greater than'.
Using the recursive formula, the first 4 terms are;
a(1) = 3, a(2) = 6, a(3) = 12, a(4) = 24
The nth term a(n) = 2n-1 x 3 (equation 1)
Equation 1 must be proven using mathematical induction. This is where I am having a problem.
Answered by Penny Nom. |
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Proof by induction |
2002-02-20 |
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From Tamaswati:
How do I prove the assertion that "the determinant of an upper triangular matrix is the product of the diagonal entries" by mathematical induction? (Before I check this assertion for a few values of n how do I rephrase the assertion slightly so that n appears explicitly in the assertion?)
Answered by Penny Nom. |
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Logico mathematical knowledge |
2002-01-23 |
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From A teacher:
How does young children's logico mathematical knowledge develop?
Answered by Walter Whitely. |
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Proof by induction |
2001-10-16 |
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From John:
Can you help me with any of these? - For any natural number n > 1, prove that
(4n) / (n + 1) < [(2n)!] / [(n!)2].
- For any natural number n > 1, prove that
1/sqrt(1) + 1/sqrt(2) + 1/sqrt(3) + ... + 1/sqrt(n) > sqrt(n).
- For any natural number n and any x > 0, prove that
xn + xn - 2 + xn - 4 + ... + x-n >= n + 1.
Answered by Penny Nom. |
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Mathematical & conventional meaning of a word |
2001-10-12 |
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From A student:
What is the mathematical & conventional meaning of a word? Like the word Rational or Median.
Answered by Penny Nom. |
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Proof by induction |
2001-09-30 |
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From Kyle:
I'm trying to learn induction and I need to see how this done please help with this problem... 20 + 21 + 22 +... + 2n = 2n+1 -1 is true whenever n is a positive integer.
Answered by Penny Nom. |
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A sequence of even terms |
2001-04-29 |
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From A student:
A sequence c is defined recursively as follows: c0 = 2
c1 = 4
c2 = 6 ck= 5ck-3 for all integers Prove that cn is even for all integers.
Answered by Leeanne Boehm and Penny Nom. |
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Induction |
2000-09-07 |
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From Joe Peterson:
How do I prove by the principal of mathematical induction?
1.n+2.(n-1)+3.(n-2)+.....+(n-2).3+(n-1).2+n.1=(n(n+1)(n+2))/6
Answered by Paul Betts. |
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1+4+9+16+...n^2 = n(n+1)(2n+1)/6 |
2000-06-01 |
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From Shamus O'Toole:
How do you derive that for the series 1+4+9+16+25.. that S(n)=(n(n+1)(2n+1))/6
Answered by Penny Nom. |
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Induction |
2000-03-16 |
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From William Tsang:
I am trying to prove a induction question Sigam r=1 n (2r -1)cube = n square (2 n square - 1)
Answered by Harley Weston. |
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Mathematical deduction and mathematical induction |
2000-03-07 |
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From Espera Pax:
What are mathematical deduction and mathematical induction, and what is the difference between them?
Answered by Harley Weston. |
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Logic and mathematical logic |
1999-10-06 |
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From Polly Mackenzie:
What is the difference between logic and math logic?
Answered by Walter Whiteley. |
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Mathematical Induction and the Derivative |
1997-03-18 |
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From Shuling Chong:
"Obtain a formula for the nth derivative of the product of two functions, and prove the formula by induction on n." Any educated tries are appreciated.
Answered by Penny Nom. |
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