how do i find the zeros of a function?

Question

mertsj · Answer

Set the function to 0 and solve that equation for x

anonymous · Answer

okay how do i find the equation from my graph?

mertsj · Answer

If you have the graph, you can get the zeros directly from the graph.  The zeros are the points where the graph crosses the x axis.

anonymous · Answer

These is no single method for it

anonymous · Answer

okay one more question... if i have a graph with a squiggly line crossing the x- axis 4 times and it tells me to use the given graph of function f to answer f(-28) how do i find the funtion of the graph?

anonymous · Answer

any ideas on where to start?

anonymous · Answer

one second

anonymous · Answer

You need to find out the y value (height/depth) of the function when x (the horizontal axis) is -28

anonymous · Answer

Finding roots is just finding when $ f(x) = 0$.

anonymous · Answer

There are various strategies for finding roots for common functions.

anonymous · Answer

There are also methods of estimating roots mathematically.

anonymous · Answer

but i dont know what the function is.. i just have a graph?

anonymous · Answer

Yeah, but you find where $x = -28$  on the graph.

anonymous · Answer

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