[TI-M] Re: How do I type in cos^2(x) type commands?


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[TI-M] Re: How do I type in cos^2(x) type commands?




> How do I type in cos^2(x) type commands?

You can't.  Use cos^2(x) = 1/2*(1+cos(2x)) = 1-sin^2(x) instead.



Just kidding, of course.  Any generic trig^y(x) is really a shortcut
notation for trig(x)^y.  This was adopted because when you're writing by
hand, you'll often want to skip the parenthesis and write something like:
.          y
.    trig x
(hope that formats right -- if you've got a monospace font, it should look
like "by hand" notation for exponentiation).  The problem is that "(trig
x)^y" can be confused with "trig(x^y)".  The solution is, when writing this
by hand, write it as "trig^y x" instead.

Of course, when using a calculator, this doesn't work nicely for two
reasons.  One is that the calculator uses trig^-1(x) as the notation for
inverse trig, while arctrig(x) is preferred when writing by hand (otherwise,
how do you distinguish between (trig x)^-1 and inversetrig(x) without using
reciprocal trig notation?).  The other has to do with CAS design and
function notation, which is probably too involved to discuss here.

But to make the long answer short, as another poster suggested, use cos(x)^2
instead.

    -Scott