Math equations

I use MathPad to scribble my equations. A slight problem is the automatic scale-function, which makes the screenshots all different in size. An example. I nicked it from some math site I forgot to save the address of. Sorry.

Say you want to solve this equation for x=3.

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That will lead to zero divided by zero. Not good. Let's take another approach. If we added a little bit to 3, say ⌂x, which is really small, the two factors wouldn't be zero. Let's see what happens if we substitute that for x:

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Now we can solve it.

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eliminating ⌂x:

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With this solution, we calculate the limit for ⌂x to zero.

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And we have our solution.

But what about another approach? As one of my physics teacher once told us, using math we didn't command at that time, "trick!".

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And let's see what it brings us.

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That's not weird, of course, it's l'Hopital's rule. For 0/0 and ∞/∞

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Okay, classes are over. You can see that I scaled them all down to the same width (400 pixels wide). But as the program fills up that space and the equation gets shorter the font enlarges. I have found no way to scale the font to a predefined size.

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addition July 9, 2015

I found MoboMath, €2,99, in the App Store and it seems to be able to handle it. It also includes LaTex and Wolfram Alpha integration and such.

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