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LAWS OF INDICES . MULTIPLYING INDICES a m x a n = a m + n.

Dec 23, 2015

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  • Slide 1
  • LAWS OF INDICES www.mathschampion.co.uk
  • Slide 2
  • MULTIPLYING INDICES a m x a n = a m + n
  • Slide 3
  • MULTIPLYING INDICES a 2 x a 3 = a 2 + 3 a5a5
  • Slide 4
  • DIVIDING INDICES (m greater than n) m > n a m a n = a m - n
  • Slide 5
  • DIVIDING INDICES a 4 a 2 = a 4 - 2 a2a2
  • Slide 6
  • DIVIDING INDICES (m less than n) m < n a m a n = 1/ a n - m
  • Slide 7
  • DIVIDING INDICES a 2 a 4 = 1/a 4 - 2 1/a 2
  • Slide 8
  • DIVIDING INDICES (ALTERNATIVE) a 2 a 4 = a -2 1/a 2 Same answer
  • Slide 9
  • INDICES IN BRACKETS (a m ) n = a mn
  • Slide 10
  • INDICES IN BRACKETS (a 2 ) 3 = a 6
  • Slide 11
  • REMEMBER Any number to the power 0 =1 9 0 = 1 100 0 = 1
  • Slide 12
  • WORKED EXAMPLE 3a 2 b 3 x 2a 4 b Separate the terms 3 x 2 = 6 a 2 x a 4 = a 6 b 3 x b = b 4 Answer = 6a 6 b 4
  • Slide 13
  • WORKED EXAMPLE (2c 3 d 2 ) 2 All the terms inside the brackets are squared 2 2 x c 3x2 x d 2x2 = 2 2 c 6 d 4
  • Slide 14
  • WORKED EXAMPLE a) Show that 4 3/2 = 8 4 3/2 means the square root of 4 cubed (4 3 ) The square root of 4 = 2, 2 3 = 8
  • Slide 15
  • WORKED EXAMPLE b), solve the equation 4 x = 8 4 4 3/2 = 8 so 8 4 = 4 4x3/2 x = 4x3/2 = 6
  • Slide 16
  • WORKED EXAMPLE Evaluate (1/3) -3 (1/3) -3 is the same as (3/1) 3 3 3 = 27
  • Slide 17
  • INDICES AND LOGARITHMS N = a x log a N = x 4 = 2 2 log 2 4 = 2 8 = 2 3 log 2 8 = 3
  • Slide 18
  • INDICES AND LOGARITHMS 100 = 10 2 log 10 100 = 2 1000 = 10 3 log 10 1000 = 3
  • Slide 19
  • INDICES AND LOGARITHMS log ab = log a + log b
  • Slide 20
  • INDICES AND LOGARITHMS log 10 8*5 log 10 8 + log 10 5 0.903 + 0.70 = 1.60
  • Slide 21
  • INDICES AND LOGARITHMS log a/b = log a - log b
  • Slide 22
  • INDICES AND LOGARITHMS log 10 8/5 log 10 8 - log 10 5 0.903 - 0.70 = 0.203
  • Slide 23
  • INDICES AND LOGARITHMS log x n n.log x
  • Slide 24
  • NATURAL LOGARITHMS The natural logarithm is the logarithm to the base e e is Euler's number, the base of natural logarithms, e approximates to 2.718 also known as Napier's constant
  • Slide 25
  • SIMULTANEOUS EQUATIONS ( BY ELIMINATION) 1, 2x - y = 2 2, x + y = 7 Add 1, and 2, (because there is a +y and a y) 3x = 9 x = 3 substitute for x in 1, 6 y = 2 y = 4
  • Slide 26
  • SIMULTANEOUS EQUATIONS ( BY ELIMINATION) 1, 2x + y = 7 2, x + y = 4 Subtract 2, from 1, (because there are two + ys) x = 3 Substitute for x in 1, y = 1
  • Slide 27
  • SIMULTANEOUS EQUATIONS ( BY ELIMINATION) 1, 3x + y = 9 2, 2x +2y = 10 Multiply 1, by 2 3, 6x + 2y = 18 Subtract 2, from 3, 4x = 8 X = 2 Y = 3
  • Slide 28
  • SIMULTANEOUS EQUATIONS ( BY SUBSTITUTION 1, y = 5x -3 2, y = 3x + 7 5x 3 = 3x + 7 (rearrange) 5x 3x = 7 + 3 2x = 10 x = 5 (substitute in 1) y = (5x5) 3 = 25 - 3 = 22
  • Slide 29
  • SIMULTANEOUS EQUATIONS ( BY SUBSTITUTION) 1,2x + y = 7 2, x + y = 4 x = 4 y Substitute in 1, 2(4 - y) + y = 7 8 -2y + y = 7 8 y = 7 Y = 1 (substitute in 2,) 1 + x = 4 X = 3
  • Slide 30
  • SIMULTANEOUS EQUATIONS ( BY GRAPHICAL INTERCEPTION)
  • Slide 31
  • WORDED SIMULTANEOUS EQUATION Bill has more money than Mary. If Bill gave Mary 20, they would have the same amount. While if Mary gave Bill 22, Bill would then have twice as much as Mary. How much does each one actually have?
  • Slide 32