Skip to main content

MIRACLE WITH MATH


1. Add two numbers
       2+2 = 4
2. Add the number repeatedly
     4+4 +4 = 12   3*4 = 12
That is multiplication
3. Now multiply repeatedly
      12*12*12 = 1728  12ˆ3 = 1728
    That is taking power

    Let us go backwards.
1. Take cube root of 1728, we get 12
                     (dividing repeatedly)
2. Divide 12 by 3, we get 4
                        (subtracting repeatedly)
3. Subtract 2 from 4, we get 2

 Addition is the basic operation, in moving forward.  But subtraction is the basic operation when moving backward.
     Using addition and subtraction, we can move to and fro in mathematical process and get the desired answers.

Calculus designed in similar fashion.
    As an example consider a freely falling body.  We know the acceleration is 9.8 m /sˆ2
1. Acceleration=g= 9.8 m/sˆ2
    if we integrate acceleration with respect to time,
 2. we get gt
  Velocity of freely falling body.
  If we further integrate velocity with respect to time.
 3. we get (1/2)g t^2  
 Distance traveled = (1/2)gtˆ2
   We get distance traveled by falling body.

Now, Differentiate 'distance traveled' with time.
1. differentiating (1/2)gtˆ2
we get
2. velocity =gt
Now, further differentiate velocity
we get
3. acceleration =g
Hence, using integration, we moved forward.  With differentiation we moved backward.
     Integration is a kind of repeated addition.  differentiation is a kind of repeated subtraction.
Why calculus?  Calculus consists mainly above two mathematical operations applied to continuously changing quantities like temperature, time, current velocity etc.  Arithmetic and algebra is applied to countable quantities like books, money, pens etc.
    Hence calculus provides easy and elegant way to get answers. 

FOOT NOTE: Let us say,  we have a curve[graph] for a mathematical function. The area under the curve is integration. The slope at any point in the curve is differentiation. y = x^2  gives a parabolic curve.
------------------------------------------------------------------------------------------------   

Comments

Popular posts from this blog

LISSAJOUS FIGURES

  Definition:  "When a particle is subjected to two sine wave motion or two oscillatory motion at right angles, the particle describes lissajous figures".      We know sine wave motion and circular motion is basically same.  Hence we draw two circles A and B perpendicular to each other.  The circle B rotates twice faster than circle A.  That is, frequency of circle B is two times than that of A.        A particle at the intersection of two circles is subjected to two sine wave motion   A and B at 90 degree simultaneously.  The particle will describe figures depending on the frequency and phase of A and B .  In our case, the ratio of frequency is  1:2 and the two waves are in phase.        To draw lissajous figures :  A moving point in both the circles are chosen.   Here we should remember; during the time taken by the circle A to complete one rotation, circle B completes two.  Hence the points are marked on the circles according to their speed.  Then straight lines

THE PARABOLA

          A jet of water shooting from a hose pipe will follow a parabolic path.  What is the so special about parabola.    Y= x^2 Draw a graph for the above equation.  It will result in a parabola.  This parabola is also called unit parabola.  Any equation involving square will yield a parabola. Example:  Y = 2x^2 +3x+3 (also called quadratic equation)    X= 2 and -2, both  satisfies the equation 4 = X^2.  Parabolic equations always have two solutions.     Any motion taking place freely under gravity follows parabolic path. Examples:   An object dropped from a moving train,   A bomb dropped from flying plane,  A ball kicked upwards.      If a beam of light rays fall on the parabolic shaped mirror, they will be reflected and brought to focus on a point.  This fact is made use of in Dish Antenna, Telescope mirrors, etc.      Inverted parabola shape is used in the construction of buildings and bridges.  Because the shape is able to bear more weight.      A plane

CASINO'S GAME

           Let us find out how the casino survives with mathematics.      Say, your friend invite you for a game of dice.  You must bet (wager) 2 dollars.  If you roll 'six' you will get back 8 dollars.  The game will go on for 30 rounds.  All sounds good.      The probability of rolling 'six' is 1/6.  Since the game will be played for 30 times, the 'expected win' is 30*1/6 = 5.  That is, you are expected to win 5 rounds out of 30.  Hence your gain will be 5 * 8 =40 dollars.  ok.  This also implies that you will loose 25 rounds.  Hence your loss will be 25*2 =50 dollars.  Your net gain will be gain-less = 40-50 = -10 dollars. For 30 rounds, the loss is -10 dollars, Hence, for one round =-10/30 = -1/3 dollars.  There will be a loss of -1/3 or 0.33 dollars per round.  It is not a fair game.     Let us make a simple formula to calculate  'Pay out per round\. The probability for a win = p The pay-out in case of win = V No. of rounds = n The expect