Question

how do I find the equation of the tangent line? Ex.) f(x)=-x^2+4x-5 at (2,-1)

Answer 1

do you mean the derivative?

Answer 2

Im not sure. It just says equation of the tangent line to the function at the given point

Answer 3

is that a homework you got from school? or did you find it by yourself?

Answer 4

from school

Answer 5

from a calculus or precalculus class I suppose right?

Answer 6

mihrib, don't give the answer, we are here to learn , not to have our homework solved

Answer 7

the equation of a tangent line of a function at (x0,y0) is:\[y=f'(x _{0})(x-x_{0})+y_{{0}}\]

Answer 8

I think (s)he doesn't know how to do the derivative

Answer 9

that's why I was asking you not to post

Answer 10

oh srry

Answer 11

i thought she knew derivatives

Answer 12

calculus.

Answer 13

yes I thought so, have they taught you how to make a derivative?

Answer 14

yes but I don't understamd at all

Answer 15

do you know derivatives?

Answer 16

see she knows derivatives

Answer 17

but she doesn;t understand them which is worse

Answer 18

okay, so let me try to explain what a derivative is

Answer 19

okay

Answer 20

i have to go anyway bi

Answer 21

what you were asked for was the tangent line to a curve that may look a little like this one

Answer 22

(sorry I'm not good drawing)
The derivative is precisely the tangent line to a curve at some specific point, in this case (2,-1)

Answer 23

it's like getting the slope of the curve