Chapter 1.4, Problem 1EQ

- Consider the following system of linear equations in the variables a,b,c,d: 5a-3b 7c - 2d = 2 2ab 2c+ 5d = -3 → (*) 4a 3b 5d = 3 6a b+2c+ 7d = −7 (a) Solve the system (*) by using Gauss elimination method. (b) Solve the system (*) by using Cramer's rule method.

Solve for a 25 55 30 a=?

9:41 … 93 Applying an Exponential Function to Newton's Law of Cooling 60. Water in a water heater is originally Aa ← 122°F. The water heater is shut off and the water cools to the temperature of the surrounding air, which is 60°F. The water cools slowly because of the insulation inside the heater, and the value of k is measured as 0.00351. a. Write a function that models the temperature T (t) (in °F) of the water t hours after the water heater is shut off. b. What is the temperature of the water 12 hr after the heater is shut off? Round to the nearest degree. c. Dominic does not like to shower with water less than 115°F. If Dominic waits 24 hr. will the water still be warm enough for a shower? Mixed Exercises ger-ui.prod.mheducation.com

Please use the infinite series formula and specify how you did each step. Thank you.

8) Solve the given system using the Gaussian Elimination process. 2x8y = 3 (-6x+24y = −6

7) Solve the given system using the Gaussian Elimination process. (5x-4y = 34 (2x - 2y = 14

33 (a) (b) Let A(t) = = et 0 0 0 cos(t) sin(t) 0-sin(t) cos(t)) For any fixed tЄR, find det(A(t)). Show that the matrix A(t) is invertible for any tЄ R, and find the inverse (A(t))¹.

Use the infinite geometric sum to convert .258 (the 58 is recurring, so there is a bar over it) to a ratio of two integers. Please go over the full problem, specifying how you found r. Thank you.

H.w: Find the Eigen vectors for the largest Eigen value of the system X1+ +2x3=0 3x1-2x2+x3=0 4x1+ +3x3=0