# Thread: I'm trying to write an equation of a tangent functio based on a graph

1. ## I'm trying to write an equation of a tangent functio based on a graph

I'm doing pre calculus on Khan academy and I am just stuck. They want me to write a tangent function based on a graph. They show how to make a graph from a function but not the other way around.

2. ## Re: I'm trying to write an equation of a tangent functio based on a graph

It is always important to look at a view critical values.

what happens to our function when x = 0 ?
what happens when y = 0
what happens to the tangent curve at pi/4 or pi/2

3. ## Re: I'm trying to write an equation of a tangent functio based on a graph

so the answer is f(x) = -tan(2x) + 1 but try and do all the working out

5. ## Re: I'm trying to write an equation of a tangent functio based on a graph

again you have to look at some critical points,

the function f(x) is of the form f(x) = Asin(bx) + C

so what happens when x = 0 ?
what about when f(x) = 0
x = sin(pi/2) ?
x = sin(pi/6) ?

you need to show some working yourself