Homework SourseFind the function f given that the slope of the tangent line
Find the function f given that the slope of the tangent line to the graph of f at any point (x,f(x)) is x?(x + 2) and that the graph passes through the point (1, 4)
Solution
Yes you take the derivative of f(x) and you get -2. This is the slope of your tangent line. Plug all you know into the formula for a line (y =mx+b). y= -2x+b Now to get b plug in the point they gave you (-1,5) 5 = -2(-1) + b 5 = 2 + b 3 = b so the formula for the tangent line is y = -2x + 3
