$21 DSCI 6001 Math for Data Science Final Exam Name: 13. (20 points) Gradient descent optimization (a) (5 points) Define your cost function for a least square problem. (b) (5 points) Give the mathematical equation of the gradient update. (c) (10 points) Assume our hypothesis is ha(X) = a0 + Xal, initial a0 and a1 are 0 and 0, respectively, and the learning rate is 0.1. With given data below, evaluate a0 and 11 in the next step. x v 1 1.2 2 1.8 3 3.2 4 3.8