I need help solving: 2+2
Sure just use your calculator!
What? what’s that thing?
Oh, its an electronic device that uses a small processor to perform arithmetical functions.
processor? what are you talking about?
look! you press some buttons and they produc–
start me from the beginning

Ok, first, an introduction to some simple logic gates.

The not gate is to be considered an inverter. It accepts one input and produces
one output. If it takes in a low voltage, it outputs to a high voltage. If it takes in
a high voltage, it outputs a low voltage.

The and gate is a gate which requires two inputs and produces one output. It is
used to check if both inputs are high, i.e. the first input AND the second
input are high. If the first input is high and the second input is high, the
output will be high. For all other cases, the output is low. Lets state these
other cases just for the record. The first input is low and the second input is
low, the output is low. The first input is high and the second input is low,
the output is low. The first input is low and the second input is high, the
output is low.

The or gate is another gate which requires two inputs and produces one output.
It is used to determine if one or both of the inputs is high, i.e. the first
input OR the second input is high. If the first input is high and the second
input is high, the output is high. If the first input is low and the second
input is high, the output is high. If the first input is high and the second
input is low, the output is high. If the first input is low and the second
input is low, the output is low. From this we can see that and OR gate will
only produce a low output if both the inputs are low. For all other cases it
will output a high voltage.

This is in contrast to our next gate. The XOR gate is known as exclusive or.
This gate is used to determine if one and only one of the inputs is high.
Meaning, either the first input or the second input needs to be high, but not
both! So, if the first input is low and the second input is low, the output is
low. If the first input is high and the second input is low, the output is
high. If the first input is low and the second input is high, the output is
high. If the first input is high and the second input is high, the output is
low.

From these we can develop a system that will add. Initially we will start off
with a half adder. By combining a XOR gate and an AND gate, we can produce a
small circuit that — what? you want to know how to make these gates?

sigh alright, the inverter can be made a couple ways.
I’d suggest using an inverting amplifier with R_f equal to
R₁. That way V_out is equal to -V_in. Oh that
is from the equation
Here take a look at this picture:

Yeah that’s a feedback setup so we can control the gain, thats how the two
resistors come into play.

Now for the AND gate, you can use a circuit made of transistors or one made of
diodes.
— what? are you serious? I have to explain transistors, diodes, and op-amps to
you now?!–

Ok the ideal op-amp is described by a few particular characteristics. You have
infinite voltage gain, infinite input impedance, zero output impedence,
infinite bandwidth, and if you input zero you get zero out, they call it zero input
offset voltage. — ideal vs. real? ok that’s a valid question but its not
really worth asking —

— what? how do you know anything about Mosfets!? are kidding me? dude, I’m not
going into semiconductor level design here! seriously! back off!

Thats it, no more! I’m not answering any more of your questions! At this rate
I’ll need to explain any number of subjects eventually ending up at trying to
explain theoretical physics! OUT! no more!
You’ve got some nerve…