Task 4

• Chronology of Phi

After that of Archimedes was value for phi, Claudius Ptolemy of Alexandria in his famous Syntaxis Mathematica ( more popularity known by its Arabian title of the Almagest), phi is given in sexagesimal notation as three - eight accent thirty double accent, which is three hundred seventy seven or three poin one hundred fourty one. This value was devided from the table gives the legths of the chords of a circle subtended by central angles of each degree and half degree. If the length of the chord of the one degree central angles is multiply by three hundred sixthy, and the result devided by the length of diameter of the circle, the above value for phi is obtained.

• Formula of abc

The early Greeks devised in genious geometrical procceses for carrying out algebraic operations. Thus Book II of the Elements, we may illustrate the method :
( a + b ) square = a square + two multiply ab + b square
by dissecting the square of side a plus b into two squares and two rectangles having area a square, b square and ab. Euclid's statment of the proposition is :
" If a straight line is devided into any two parts, the square on the whole line is equal to the sum of the squares on the two parts together with turice the rectangle contained by the two parts".

• Volume of Cone

If was knowed with radius (r) and this height (t), to find of cone volume base area is multiply of height. When base area is a circle, cone volume is phi multiply of square radius and multiply of height.

• How to prove that in sigitiga amount on degrees 180 degree!

Angle DCE = angle CAB (because sides)
Angle BCE = angle ABC (as opposed in)
Angle ACB + Angle BCE+ Angle ECD located in one line (180degree)
Angle ACB + Angle BCE+ Angle ECD = 180degree
Angle ACB + Angle ABC + Angle CAB = 180degree
Provently.

• Probability appearing sum figure more than six from two dice was played one's.

There are twentty one of the sum figure more than six from two dice was played. So, probability figure appearing more than six was tweenty one devided thirty six.

• Drawing Cube
  

To draw a cube of if known by the element,firstly paint the area of frontal ,after that find the our side of frontal,then make it’s angle of deviation or angle;corner of surut,after that get big of its size measure hence we make the side of ortogonal with the angle;corner withdraw and comparison ortogonal hence we get the length of side of ortogonal.from own of angle;corner dot of our area frontal make the side of ortogonal,the size of inclination must appropriated with angle of surut,and the length as according to comparison ortogonal.So by connecting from the own of dot,we get a picture develop build the cube.