Sunday, August 30, 2009

Post #2

The second week of calculus is over! Although I think Calculus is still one of my hardest classes, it's getting better. I am understanding everything a lot better, and I've learned that it's good to ask questions.

Something I understoood this week was the natural log properties. You simply plug everthing into the formula and simplify. Let's say we have ln(x^2). You plug into the ln formula, 1/u * u', and you get 1/x^2 * 2x. When you multiply you get 2x/x^2 which simplifies to 2/x (you cancel the x's). I also understand that you may have to deal with multiple formulas in one problem. An example would be ln(x/(x^2 + 1)). In this problem you can see that you have to deal with natural log and quotient rule. You would plug it into 1/u * u' first and then into the u prime you would do the quotient rule, (vu' - uv') / v^2.

I also still get everything from last year with just normal logs. Take log 1000 = x. You would take away the log and swap 1000 and x. You then have 10^x = 1000. So from algebra you would know that 10^3 = 1000. So x = 3 would be your answer.

Something I don't understand is the difference from u^n and a^u. Take the example (ln x)^4. Would you plug it into u^n = nu^(n-1) or a^u = a^ulna * u'? I am still unsure about the whole concept.

Hope this helped somebody.
Ryan.

1 comment:

  1. a^u is only used when a is a number.
    u^n is what you would use for (lnx)^4 because that is NOT a number.

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