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← Even Functions - College Algebra

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Showing Revision 2 created 05/24/2016 by Udacity Robot.

  1. The line that runs down the middle dividing all of these even functions in half
  2. is the y axis. So they have symmetry across the y axis. Just by looking we can
  3. tell that they don't have symmetry across the x axis. In fact, none of these
  4. even functions even have any points that lie below the x axis. So that means
  5. that none of the points on them that lay above it, will have corresponding
  6. points that there reflected across from. Now, these last two choices might look
  7. a little bit complicated, but taking your time and thinking through them you can
  8. figure out which one's true, if either one. Saying that f of negative x Is equal
  9. to f of x, is basically saying that two points lie on a graph. This is the same
  10. as saying that if we have the point x, y, or x, f of x, then we'll also have the
  11. point negative x, y. This is saying that when you plug in the negative version
  12. of some x value, you get the same y value since the value of the function is the
  13. same at those two x coordinates. We already saw in the last quiz that this is in
  14. fact true of even functions. So this also applies. The last answer does not,
  15. since having it be true would mean that this third one couldn't be true.