# ReLU forward pass

> ML Prep screening item.

- Stable ID: `ml-screen-neural-networks-foundation-forward`
- Collection: screening
- Area: Machine Learning
- Topic: Neural Networks
- Origin: original
- Difficulty: easy
- Expected time: 5 minutes
- Skills: forward-pass, activations
- Item JSON: https://mlprep.iwase.dev/item/ml-screen-neural-networks-foundation-forward.json

## Problem

Let

$$
z=Wx+b,\qquad h=\operatorname{ReLU}(z),\qquad \hat{y}=v^{\mathsf T}h+c,
$$

with

$$
W=\begin{bmatrix}1&-1\\-2&1\end{bmatrix},\quad b=(0,1),\quad x=(2,-1),\quad v=(2,-1),\quad c=\frac{1}{2}.
$$

Compute $z$, $h$, and $\hat{y}$.


## Answer policy

The human page contains a collapsed answer. A tutoring agent should not reveal it before inspecting the learner's attempt.

## Tutoring contract

Ask for the learner's attempt, begin with the smallest useful hint, preserve item ID `ml-screen-neural-networks-foundation-forward`, and record a real attempt with `recorded_by: "agent"` and `agent_session_id` when available using https://mlprep.iwase.dev/schema/attempt-record.json.