If f(x+5)=f(x) for all values of x, then f(x)=0 for how many different values of x between 0 and 12?
@jim_thompson5910
what f(x+5)=f(x) means is that the function repeats itself every 5 units (so the period of this function is 5) what this means is that if f(x) = 0, then this could happen at most 3 times (at x = 0, x = 5 and x = 10) however, it could easily be twice (say at x = 3 and x = 8 since x = 13 is out of the interval) there's no way it could happen exactly once (go ahead and try different x values and you'll see this is true) however, it's possible that f(x) = 0 is not true for any values of x, so there could easily be no solutions for f(x) = 0
There's a strange graph to go with this, if you'd like to see it. A) Eight B) Nine C) Ten D) Eleven E) Twelve
go ahead and post it
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