7. (15 points) Consider the problem of building a classifier for the following data using support
vector machines:
$x_1$
-1
-1
1
1
1
3
$x_2$
-3
1
-1
1
2
2
y
-1
-1
-1
1
1
1
Note that $x_1$ and $x_2$ denote the predictors and $y$ denotes the class label. Suppose that the decision
function is given by, $D(x_1, x_2) = ax_1 + bx_2 + c$, where $a$, $b$ and $c$ are parameters.
(a) Formulate the primal problem.
(b) Formulate the dual problem.
(c) Given that $(-1, 1)$, $(1, -1)$ and $(1, 1)$ are support vectors. Find the decision function.
