calc math prob?

Question

let f(x)=Ax + (B/x^2) where A and B are constants. Find values for A and B so that the line y=2x+1 is tangent to y=f(x) when x=-1.

I have no idea how to do this./

Answer 1

Take the derivative of f(x) and set it equal to 2 (the slope of the given line). Now notice that the line passes through (-1, -1) so that, to be tangent to f(x) the value of f(x) must also be -1 at x=-1.
That gives you two equations in the two unknowns (A and B) so you solve for them like any other system of linear equations.
No. I'm not going to do it for you. You do it and you'll see how it works ☺

Doug