Apologies for the forum's recent errors. A firewall setting went bad and blocked much access. Everything should be fine again now.

Thank you for your patience.

- Sat May 07, 2016 12:59 pm
- Forum: News
- Topic: firewall settings
- Replies:
**0** - Views:
**2146**

Apologies for the forum's recent errors. A firewall setting went bad and blocked much access. Everything should be fine again now.

Thank you for your patience.

Thank you for your patience.

- Thu Mar 10, 2016 6:11 pm
- Forum: Trigonometry
- Topic: 10 Trigonometric Equation
- Replies:
**1** - Views:
**985**

I am solving a paper with 45 questions and out of which i have 10 questions for which i am not getting solutions. If at any cost you are having solution please let me know. Although the questions are in images. Please check the link and let me know if you can find the solution. Can even pay if you ...

- Sat Jan 30, 2016 10:14 pm
- Forum: Calculus
- Topic: Interpolation of a series of data points via Chebyshev approximation
- Replies:
**1** - Views:
**1028**

Lacking specifics, it is difficult to respond. I suspect that the responses posted **here** are about as good as you'll get. Good luck!

- Thu Jan 21, 2016 6:15 pm
- Forum: News
- Topic: EU-compliant "cookies" notice added
- Replies:
**0** - Views:
**2191**

The learning forums, in addition to the rest of the Purplemath site, have added an EU-compliant notice about privacy and cookies. If this is the first time you've logged in since 20 January 2016 (or if you have cleared your cookies since that time), you'll see the notification bar across the top of ...

- Sun Jan 10, 2016 3:01 am
- Forum: Matrix (Linear) Algebra
- Topic: Decoding matrix
- Replies:
**3** - Views:
**1548**

Hi, the question from my work asks to find out coding matrix and it is represented as below * * * 1 0 * * * 0 1 It states use row operations to reduce the following matrix to the above form 1 1 1 1 1 1 2 3 4 0 and it a mod 5 matrix. Having the actual (full and exact) text of the original exercise w...

- Sat Jan 09, 2016 11:44 pm
- Forum: Matrix (Linear) Algebra
- Topic: Decoding matrix
- Replies:
**3** - Views:
**1548**

I am stuck on reducing the following matrix. It is supposed to be in H = CI format where C = Coding matrix and I = Identity matrix 1 1 1 1 1 1 2 3 4 0 and its a mod 5 matrix What do you mean by "reducing" this matrix? I am wondering if anyone could help me reduce the above matrix to following forma...

- Sat Dec 19, 2015 1:05 am
- Forum: Matrix (Linear) Algebra
- Topic: Find basis and dimension of a vector space
- Replies:
**4** - Views:
**1388**

Could you respond on solving this problem? Where are you stuck with what they gave you elsewhere? Let p(x) = a_0 + a_1 x + a_2 x^2 + a_3 x^3 be a polynomial of degree 3. The polynomial p(x) is in W if and only if a_0 + a_1 + a_2 + a_3 = 0. Thus it easy to see that the polynomials p_1(x) = 1 - x, p_...

- Sat May 23, 2015 9:07 pm
- Forum: Intermediate Algebra
- Topic: Substituting a Zero into a negative variable
- Replies:
**8** - Views:
**1811**

here is what i did: http://postimg.org/image/nicftcc37/ For others viewing this thread, the text in the image is, roughly, as follows: 1x^2\, +\, 0x\, +\, 1 substituted into \dfrac{-b\, \pm \, \sqrt{b^2\, -\, 4ac\,}}{2a} =\, \dfrac{-(0)\, \pm\, \sqrt{(0)^2\, -\, 4(1)(1)\,}}{2(1)} which reduces to t...

- Thu May 21, 2015 6:29 pm
- Forum: Calculus
- Topic: Is it possible to evaluate this integral without a calculator?
- Replies:
**3** - Views:
**1939**

Integral[x=0 to 2pi] [([(sin(x)+3)-ln(x+1)][cos(9x)+5])+(3/4)[pi[(sin(x)+3)-ln(x+1)][cos(9x)+5]]]dx Is the integral (posted above as ASCII "art") meant to be as follows? . . . . . \int_{x = 0}^{2\pi}\, \left[\, \left\(\, \sin(x)\, +\, 3\, -\, \ln(x\, +\, 1)\right)\,\left(\cos(9x)\, +\, 5\right)\,\r...

- Thu May 14, 2015 10:14 pm
- Forum: News
- Topic: forum upgrade in progress
- Replies:
**1** - Views:
**3545**

The upgrade was completed, and then updated. A recent (and possibly resumed today) DDoS attack made the site and this forum slow to respond, and many files were damaged somehow, which "broke" LaTeX for a while. But things seems to be working again now.