## Wednesday, May 27, 2009

### Scribe and Bob Post

 Delicious For Conics – Click here!Quite a number of people have asked to see my Counting test, so I just scanned it and decided to post it here.Page 1Page 2Page 3Page 4I found this unit extremely easy. The stuff looked like nonsense and garbage to me from the start, but when I actually looked at the stuff, I realized that I was wrong. The folding of the papers did not help me however. Nevertheless, it was Mr. K’s method to help us understand every one of the conic sections. You must basically understand the anatomy of each conic section. That is the key to solving the questions. Other than that, the unit test should be easy. Well, I hope it is.WATCH OUT WHEN DOING/DRAWING THE VERTICES AND FOCII. IT’S OBVIOUS THEY’RE NOT THE SAME, BUT EVEN PEOPLE THAT KNOW THAT CAN MAKE MISTAKES WHEN DRAWING THEM. SOME PEOPLE USE THE FOCII AS THE VERTEX BY ACCIDENT OR ADDRESS THEM INCORRECTLY WHEN ANSWERING QUESTIONS !!!!!HyperbolaThe transverse axis extends from the vertices of the hyperbola. This does not have a fixed orientation. It can be either horizontal or vertical. It can be found by using “2a.” Two semi-transverse axes complete a full transverse axis.The conjugate axis is the perpendicular bisector of the transverse axis, meaning it cuts the transverse axis in half at a 90 degree angle. This does not have a fixed orientation. It can be either horizontal or vertical. It can be found by using “2b.”Two semi-conjugate axes complete a full conjugate axis.For the conjugate and transverse axes, watch out for what the question asks for. Some may ask for the “semi axis” while some may ask for just the “axis.”Video on HyperbolaWorksheet on HyperbolaMy questionOne focus is at (-5,0) and the nearest vertex is at (-3,0). What is the orientation of the hyperbola?HorizontalGiven a hyperbola, let’s say you have the points of the conjugate axis. You also have a point (99,1000) which is located on the hyperbola. How would you find the equation?Use the equation of the hyperbola to plug in your x and y values with (99,1000) while you obtain A or B with the conjugate axis. This leaves you with one variable, which is A if you chose B or B if you chose A. Isolate that variable and bam.EllipseVideo on EllipseWorksheet on EllipseThe major axis is the longest of the axes. Two semi-major axes complete the major axis.The minor axis is the shortest of the axes. Two semi-minor axes complete the minor axis.CircleVideo on CircleWorksheet on CirclesThe circle is like the ellipse’s brother. They’re pretty much the same except the circle has radii equidistant from the circumference to the center of the circle.ParabolaVideo on ParabolaWorksheet on ParabolaThe parabola is very easy to understand. There is one focus which is the same distance as the directrix from the vertex of the parabola.QuestionIf the focus is to the left of the vertex, what direction does the parabola open?It opens to the left.ProbabilityThe next scribe is DION!!