"Some really hard problems" That is exactly what our teacher wrote on the top of this worksheet we got for homework. I'm in Calc AB and our teacher gave us 12 really evil problems. I'm stuck just on the first problem: Evaluate lim (x/x-3)(Intergral of sint/t dt from 3->x) x->3 Sorry if the notation is kind of weird, I don't know how to get half these symbols on the computer. Anyway, I first tried to find the limit of just x/x-3 and it's undefined. Then I tried finding the intergral of sint/t dt but it just kept going around in a circle from (ln t)(sin t)-the intergral of ln t (-cos t)-(1/t)(-cos t)-the intergral of 1/t sin t...and so forth. I believe i saw somewhere that if an intergral keeps repeating it's undefined, but my teacher hinted that there's a definate solution to it. Can someone help me? This assignment is due Thursday, and I haven't a clue as how to go about solving these. I'll need help on some of the other problems too, which I'll post later. Someone please respond soon!! I don't want to fail!!