by Lemonds » Tue May 08, 2012 5:31 pm
Thanks for your response! Honestly, the problem that sparked my question is #58 on the District 2 Math test. It reads, "A right traingle has a hypotenuse of length 10". If one of the acute angles is decreasing at the rate of 5 degrees per second, how fast is the area of the triangle decreasing when this acute angle is 30 degrees? (nearest tenth)" The answer is B) 2.2 in^2/sec.
I probably should of put this in the Math forum, but I've seen many more related rate problems on Calculator than I have on Math. I see how to get the answer, just take the derivative of .5*h^2*sinx*cosx (and remember it's in radians), but it just takes me so long to derive the function. Is there any way to put this into an 89 or something, or do I just have to get extremely fast at doing related rate problems?