This is a part of a problem that I'm having, and I'm unclear how to do this particular step. I'm dealing with a ridged regression and I need to minimize the equation
$$\sum (Y_i - \beta^Tx_i)^2 + \lambda\sum\beta_j^2$$
The question says I need to find $\beta$ that minimizes this and I'm not sure how to do that because I have a vector.
How do I do this?