Lecture 16: Arithmetic 1 Revision

Addition, Subtraction, Multiplication, Division to add st to st [œd]; add up two numbers to subtract st from st [s  b’trœkt] to multiply st by st [maltiplai] to divide st by st [di’vaid] = 9 (six plus (and) three equal(s) (is) (are) nine) = 3 (six minus three equal(s) (is) (are) three) (three from six …) 6 x 123 = 738 (6 times (multiplied by) 123 equal(s) (is) (are) 738) 738 / 123 = 6 (738 divided by 123 equal(s) (is) (are) 6)

Power, Root 2 2 = 4 (2 squared equals (is) (are) 4) 2 3 = 8 (2 cubed equals (is) (are) 8) 2 4 = 16 (2 to the fourth (to the power of four) equals (is) (are) 16) 2 5 = 32 (2 to the fifth (to the power of five) equals (is) (are) 32) Power is a result of raising a base to an exponent [iks’p  un  nt]: 8 is a power of 2 since 2 3 = 8  2 is a base, 3 is an exponent  9 = 3 (the square root of 9 equals (is) 3) 3  27 = 3 (the cube root of 27 equals (is) 3) 4  256 = 4 (the fourth root of 256 equals (is) 4) 5  32 = 2 (the fifth root of 32 equals (is) 2) Martin Dvořák:

Fractions Fraction [frœkš  n] is a ratio of numbers or variables. The following should be read as three fifths, two thirds, nine tenths respectively: in the first fraction represents a numerator and 5 denominator Equation [i’kweiš  n ]: = = represents the common denominator of the two fractions (the least common multiple [maltipl])

Fractions - Variables 2x +3 (two x plus three over 3) 3 Equation: 3x + 2x = 9x + 10x = 19x

Sine, Cosine sin, sine [sain]; sin  [sain of œlf  ] cos, cosine [k  usain] hypotenuse [hai‘pot  nju:z]

Rounding to round a number up x to round a number down Example: rounded to two decimal [desim  l] places is rounded to three decimal places is 2.888

Signs. - decimal [desim  l] point < - inequality sign (is less than) + - plus sign > - inequality sign (is greater - - minus sign than) x - multiplication sign $ - dollar sign / - division sign & - ampersand [œmp  sœnd] = - equal sign % - percent symbol : - colon ; - semicolon | - vertical line ( ) - parentheses {} - braces, curly brackets [] - square brackets

Homework Specialist reading: Storage Devices