Consider the differential equation
dxdy=y2−x
with solution curve that passes through the point (0,1). A student wishes to approximate the value of y(0.1).
(a) Evaluate dxdy at (0,1).
(b) Compute an explicit expression for dx2d2y in terms of x and y. Then evaluate dx2d2y at (0,1) and state its sign.
(c) The student uses a single tangent‐line step of size h=0.1 beginning at (0,1). Without carrying out any numerical calculation, determine whether this approximation of y(0.1) is greater than or less than the true value. Justify your answer using the concavity you found in part (b).