AP calculus question

<p>if f(3) = 2 and f'(3) = -2, and g(x) is the inverse of f(x), what is g'(2)?</p>

<p>Your message:</p>

<h1>if f(3) = 2 and f'(3) = -2, and g(x) is the inverse of f(x), what is g'(2)?</h1>

<p>Background:</p>

<p>Suppose g(x) = inv of f(x), then the following property holds true:
f(g(x)) = x</p>

<p>Derivative of both sides: (use chain rule)
f'(g(x)) g'(x) = 1
therefore g'(x) = 1/f'(g(x))</p>

<p>So....... using that info:
g'(2) = 1/f'(g(2)) = 1/f'(3) = 1/-2 = -1/2</p>

<p>that's a calc question?...lol. looks more like algII/trig..o.o"</p>

<p>Unless you learned what the notation</p>

<p>f'(x) </p>

<p>means while in algII/trig (which I doubt)
It's calculus :)</p>

<p>I never heard of derivatives being taught in any algebra class. Do some algebra classes do that?</p>

<p>Derivatives topic is not in Algebra, even though some alg. classes MIGHT teach them (like they're finished with program in two months) -- it is not Algebra.</p>