dy 13. Let y = f(x) be the solution to the differential equation = x + 2y with initial condition f(0) = 2. What is dx the approximation for f(-0.4) obtained by using Euler's method with two steps of equal length starting at x = 0 ? (A) 0.76 (B) 1.20 (C) 1.29 (D) 3.96

Plant Growth Researchers have found that the probability P that a plant will grow to radius R can be described by the differential equation dPdR=4DRP2 where D is the density of the plants in an area. Source: Ecology. Given the initial condition P(0)=1, find a formula for P in term of R.