p=any number ending in 3

check p is not a square

where a+b is a factor and a-b is another factor

Number ending in 3: factors end in 1 and 3, or 7 and 9. Times by 27 factors now end in 1 and 1.

f=10c+1 L=10d+1

b=(10c+1-10d-1)/2=5(c-d)

Welcome to the forum!

You're right I don't think it proves anything yet.

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Solution always can be written, for example.

]]>You can substitute any integer in place of the 6's and get the correct subfactorial value.

]]>I'll be 20 next time I take this test. I wish I could have started a year or two ago but my highschool education was complicated and inefficient. Safe schools were too expensive and affordable schools were too dangerous. (shootings, drug problems, etc.)

Wait, where do you live?

]]>to differentiate the following

start with the following

then take natural logs of both sides

diferentiate both sides

NOTE 1: since I could seem to write the derivative of f(x) and g(x) as f'(x) and g'(x) I had to change the to h(x) (for g'(x)) and i(x) (for f(x)

NOTE 2 this derivative was done using the chain rule and the product rule

multiplying by y

and sustituting

]]>To solve:

Define the following 8 variables A, B, C, D, E, F, G and H.

then the roots are:

]]>Uh huh. Where do I download it?

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