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    Graphing Functions aoife0509

    How do you do functions i dont understand how to get f(x) and then graph it

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      Alex F

      A function relates an input to an output

      If f(x) = - x + 1 then (x) = input - x + 1 = output Here x just signifies the input it can be any letter or number

      f(x) = - x + 1 f(q) = - q + 1 f(A) = - A + 1

      If our input x = 4 then we have

      f(4) = - 4 + 1 = 13

      A function can also be expressed using y or f:x-> f(x) = - x + 1 y = - x + 1 f:x-> - x + 1 The 3 expressions above mean the exact same thing There are 3 types of basic graphs Linear - This graph is a straight line Exponential - This type of graph grows and shrinks very quickly Quadratic- This graph is a parabola which means it makes a u or n shape

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      IrishJuniorCert

      I think Alex is complicating this a bit much.

      As far as I'm aware, you fully understand functions, just not how to graph them.

      Well, it's pretty easy once you know that:

      x = your input.

      y = your output.

      so say your x = 4. Then on the X Line, you are +4 across.

      Input: 4

      Function: x + 1

      Output: 5

      So the x value is 4 and the y value is 5. You can now graph your line. As Alex said, there will be much more complex types of functions where x will be squared and this will give you a parabola.

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      aoife0509

      Thanks for your help i understand it a bit more nw

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      Ciara231001

      im stuck on it too tbh

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      Me

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