MATH 320 Midterm: MATH 320 UW Madison 320pExam1 Fall 17
Document Summary
Directions: do all the work on these pages; use reverse side if needed. Show all the details of your work, and clearly cite the theorems you use. Answers without accompanying reasoning will only receive partial credit. No books, notes, or calculators, and please write legibly. Solve the following odes: (10 points). (x4 + 2) = yx3. dy dx: (15 points). x dy dx. A 200 liter tank initially contains 100 liters of salt water with 20 kg of dissolved salt. A solution with 1 kg/l concentration of salt enters the tank at a rate of 3 l/min, mixes instantaneously with the solution in the tank, and exits the tank at a rate of 1 l/min: (5 points). Write down the corresponding ode initial value problem for the amount x(t) of salt in the tank at time t: (20 points). Use elementary row operations (and clearly indicate every operation used) to solve the linear system:
