How can you tell if a function is even or odd?

If you have a plot of the function, you can look at its symmetries. If the plot to the left of the y axis is the mirror image with respect to the y axis of the plot to the right, it's an even function. If the plot on the left is a mirror image with respect to a diagonal line going from the top left to the top right of your axes system, it is an odd function. (some example plots: f(x)=x2, g(x)=cos(x), ...)If you only have the function's equation, you can try replacing x by -x and see how the function reacts. If f(-x)= f(x), f is an even function, and if f(-x)= -f(x), f is an odd function. For example, (-x)2=x2 and so f(x)=x2 is an even function of x.

FD

Related Maths A Level answers

All answers ▸

The point P (4, –1) lies on the curve C with equation y = f( x ), x > 0, and f '(x) =x/2 - 6/√x + 3. Find the equation of the tangent to C at the point P , giving your answer in the form y = mx + c. Find f(x)


Find where the graph of y=3x^2+7x-6 crosses the x axis


Find dy/dx when y = 4x^1/2


The curve C has the equation y=3x/(9+x^2 ) (a) Find the turning points of the curve C (b) Using the fact that (d^2 y)/(dx^2 )=(6x(x^2-27))/(x^2+9)^3 or otherwise, classify the nature of each turning point of C