Start with an easy (w)in

Aug 15, 2026

Week 1

Short

Easy

Neural Networks

Start with an easy (w)inWeaver’s Weekly #1

Solve interactively onweavergoldman.com/weekly

How many hidden ReLU units $n$ does it take to draw this W?

Find the weights and biases needed to produce the W.

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n

(hidden units)2

h_{1}

w

b

h_{2}

w

b

Output perceptron

v_{1}

v_{2}

c

Reveal solution

Start with an easy (w)inWeaver’s Weekly #1

Full write-up onweavergoldman.com/weekly

h_{1}

w = -4

b = 1

h_{2}

w = 4

b = -1

h_{3}

w = 8

b = -4

h_{4}

w = 8

b = -6

There are multiple possible solutions, but a solution of this type will have 4 hidden units.

One way to arrive at a solution is to start with the first hidden unit with a slope of -4 and a y-intercept of 1.

This creates the downward line from (0,1) to (0.25,0). The line is then cut off by ReLU, which is why the line stops at (0.25,0).

The other tricky aspect is that if you start this way, the output of the third hidden unit will need to be multiplied by -1, which is why the weight from the third hidden unit to the output is -1.