Recent content by sgnmath

I totally agree with the last post. I thought there was a trick or an elegant way to do it (while avoiding doing integration by hand), but there was none. It is dumb only when I realized that getting the answers involves knowing which command/syntax to use in TI calculator.

hence my comment in my first post: This is ?, where initially ? was Dumb but I changed it.

from the original post: " * Do not try to integrate \sqrt(4-x^2). * Use a calculator "

OK. Good. Since you figured that out. Here is the math. Find k so that $$\int_o^k 16 \sqrt(4-x^2) dx = \int_1^2 16 \sqrt(4 - x^2)dx = 19.6539$$. The first integral is not a constant, but the second one is. To be precise (and to see technology can be slo), with TI83 or 84: in Y1, type the first...

That doesn't help. They are not supposed to integrate!

This is ?. It is much nicer if you (or WE) are allowed to integrate. But TI89: nsolve(nInt(16 sqrt(4-y^2),y,0,x)=19.6539,x) where x is your k. nSolve is under F2, nInt is under F3, nSolve(nInt(16 \sqrt(4-y^2), y,0,x) = 19.6539, x). You might want to do it with without n, but it takes longer...