Maths End of year

N 1 2 3 4 5 6 7 8 2N+3 5 7 9 11 13 15 17

19

Find the formula for:

5, 8, 11, 14, 17...

Step 1.  Find difference between each term.  In this case it is 3, This means the formula is 3n (3 x n)

Step 2.  Find the number before the first term

  2,  5,  8,  11,  14,...

-3                        +3

This is the number we have to add on to what we found in step 1. (3n)

So the formula is 3n+2

Functions is basically the Nth term but written differently

Eg.  x ---> 2x  =  Y/2

⅕ + ⅖ = ⅗

  ↖↗       ↑

Add         denominator

These      stays the same

But what happens if the denominator is the same?

7/9 + 13/18

Find a number that is a multiple of both numbers

9x2=18

18x1=18

whatever you do to the top you do to the bottom

7  x2            14 13 x1 13

-         =    --                 --  =  --

9  x2            18 18 x1        18

so...

14     13 27

--  + --    =   -- or 9/18

18     18 18