We had an interesting suggestion today 4th hour on determining whether a function is even or odd without using a graph. Let’s take another look.
The suggestion was to simply plug in a number into the function and then plug in its opposite and see if that value fits the definition of even or odd. So, for example, if `f(-2)=-f(2)` then the function is odd. Or if `f(-2)=f(2)` then the function is even.
Look at the following graph and tell me the fatal flaw in this method.
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xmin=-5; xmax=5; xscl=1; ymin=-10; ymax=10; yscl=2;
axes();
plot(-(13/30)x^3+(47/30)x^2+(26/15)x-(64/15));
endagraph