Exact Answers

Part 1 (1-13): Convert between degrees and radians, graph angles in standard position, and find coterminal angles in both radians and degrees. Find the exact value (the ratio between the sides) of different special angles (30°-60°-90° and 45°-45°-90°) by evaluating the trigonometric function (sin, cos, tan, csc, sec, cot). Part 2 (14-20): More evaluating questions continued from part 1. Find the trigonometric ratio given: (1) a point (x, y) on the terminal side of an angle in standard position, (2) a triangle, (3) another trig ratio. All answers are left as exact (simplified radical form). Part 3 (20b-23): Using trig functions and inverse trig functions to find missing angles or sides in right triangles. Now we’re using the calculator and approximating our answers. Part 4 (24a-c): We leave the comfortable world of right triangles behind and enter a world with no 90° angles and no hypotenuses. So, we must use law of sines and law of cosines to find missing sides and angles and solve triangles. Beware of the SSA situation because it doesn’t mean there is only 1 triangle possible; there might be two or it might not even be a triangle. Part 5 (24d-25): We continue solving triangles with the law of sines and law of cosines. We also find the area of non-right triangles using two different area formulas.

I recently won two goldfish from the fair and have since placed them in a 2-gallon tank. I put in about 3 mL of Water Conditioning to get rid of the chlorine in my tap water and washed out the the tank and the gravel before placing the fish in the tank. I had been feeding them flakes. Everything was fine the first day, but then on the second day my first goldfish starting to act strangely. It started to bump itself against the walls of the tank, which gave it a bloody mouth and gills. It was also swimming erratically, almost to be writhing in pain. Then just last night I found it floating at the bottom of the tank, dead. Now today i noticed that my other fish started to do the exact same thing( Its dorsal, pectoral and anal fin have a black line that I’m sure wasn’t there before. Also I think i see some patches of white on one of its sides, but I’m not sure if it’s just the coloring of its scales.) . Please someone tell me what this condition is and what i can do to fix it. I’d hate to have to flush another fish again after it suffered a slow and painful death. You can respond in the comments, at Yahoo! Answers answers.yahoo.com

Chief Official White House Photographer Pete Souza answers your questions and talks about his favorite photos in a live web chat. October 28, 2010