+118742 
+118742 @@ End of Day Wrap Fri 2 /1/15 Sydney, Australia Time 3:40pm ♪ ♫
Hi every one. The new year is not new anymore. How sad. 
Still our questions continue and today there have been some really good answers from Geno3141, CPhill, SelenaPubblT. Tetration and Rosala. Thanks everyone.
Interest posts:
Polar co-ordinates. Thanks Geno
http://web2.0calc.com/questions/what-are-the-polar-coordinates-of-5-6
1) Differential Equation. Thanks Chris and Geno
http://web2.0calc.com/questions/hello-could-you-advise-me-how-to-solve-this-please-u-t-u-t-k
2) Explaining the unit circle. Geno and Melody.
http://web2.0calc.com/questions/how-does_1
3,4,5) ome great calculus Answers from Chris. Thanks Chris.
http://web2.0calc.com/questions/please-solve-this-for-me_3
http://web2.0calc.com/questions/please-solve-this-for-me_2
http://web2.0calc.com/questions/please-solve-this-for-me
6) Perpendicular bisector Thanks Geno
♫♪ ♪ ♫ ♬ ♬ MELODY ♬ ♬ ♫♪ ♪ ♫
+118742
I KNOW THE YEAR IS NOT SO NEW ANY MORE BUT
THESE NEW YEAR POSTS WERE WRITTEN ON NEW YEARS DAY
IF YOU HAVE NOT DONE SO ALREADY IT WOULD BE REALLY NICE IF YOU TAKE A LOOK.
IN MY MESSAGE I ADDRESS INDIVIDUAL MEMBERS AS WELL AS ALL MEMBERS COLLECTIVELY
I WANT YOU TO KNOW HOW VERY APPRECIATED YOU ALL ARE.
Merriment wishes for the new year
http://web2.0calc.com/questions/happy-new-year-everyone Thanks Rosala you are always so thoughtful
http://web2.0calc.com/questions/happy-new-year-everyone_1 Melody
♫♪ ♪ ♫ ♬ ♬ MELODY ♬ ♬ ♫♪ ♪ ♫
+118742 -3cos²(-π/2)=0 also
I would like to try and explain something to you.
Look at this page
http://www.mathsisfun.com/sine-cosine-tangent.html
There is an interactive unit circle at the bottom of the page. You can choose radians or degrees.
Now the hypotenuse of the triangels is the radius of the cirlcle which is 1
The sine of the angle is given by the y value on the circumference of the unit circle
The cos of the angle is given by the x value on the circumference of the unit circle.
The tan of the angle is given by the y value over the x value on the circumference of the unit circle.
Play with it and really try to understand the concept. It will help you enormously if you really understand this.
At pi/2 and at -pi/2 the x value is 0 so cos of these angles will be zero!
Sine will be 1 and -1 respectively. Tan will be undfined - you cannot divide by 0 :)
