The function f (x) has the value f (-1) = 1. the slope of the curve y = f (x) at any point is given by the expression dy/dx = (2x + 1)( y + 1) 1. write an equation for the line tangent to the curve y = f (x) at x = ? 1. 2. use the tangent line from part a to estimate f (? 0.9) 3. use separation of variables to find an explicit or implicit formula for y = f (x), with no integrals remaining. 4. what is the limit of f(x) as x approaches infinity?