<p>This is true for quasilinear utility function. Suppose
$$U = d + V(x),
$$
where $d$ is the numeraire. The budget constraint is given by $p_x x + d = I$. The utility is then
$$U = I - p_x x + V(x).$$
Maximizing this, we have the following FOC: $p_x = V'(x)$. That is, for a given $x$, my willingness to pay is $V'(x)$, the marginal utility.</p>

CC BY-SA 3.0
2018-01-13T19:32:17.933Z
Thx, I will check your answer shortly!
babipsylon
CC BY-SA 3.0
2018-01-12T04:26:57.213Z
2018-01-12T04:26:57.213Z
Art
<p>Can one say that the demand curve equals the marginal utility function? I have one course where this is stated.</p>

<p>However, the demand curve dan be derived from combining the utility function with the budget curve, while varying the price of the one good of interest and plotting the corresponding quantities found from the equilibria in the goods space and the budget curve.</p>

<p>While I do understand this method, I don't understand how the demand curve can be seen as the marginal utility function using this method (or any unknown other).</p>

<p>Please enlighten me :).</p>

CC BY-SA 3.0
2018-01-09T22:37:25.897Z
here they say they are the same but... not a very clear answer if u ask me  https://www.quora.com/Are-the-marginal-benefit-curves-and-demand-curves-exactly-the-same#
babipsylon
<utility><supply-and-demand><price><marginal>
relation between the demand function and the marginal utility function
babipsylon
# relation between the demand function and the marginal utility function

(Asked by: username_0 on 2018-01-08)

Can one say that the demand curve equals the marginal utility function? I have one course where this is stated.

However, the demand curve dan be derived from combining the utility function with the budget curve, while varying the price of the one good of interest and plotting the corresponding quantities found from the equilibria in the goods space and the budget curve.

While I do understand this method, I don't understand how the demand curve can be seen as the marginal utility function using this method (or any unknown other).

Please enlighten me :).

**Tags:** utility, supply-and-demand, price, marginal

> **Comments:**
> **username_0**: here they say they are the same but... not a very clear answer if u ask me  https://www.quora.com/Are-the-marginal-benefit-curves-and-demand-curves-exactly-the-same#  

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## 1 answers

### Answer by username_1 on 2018-01-12. Score: 2 | Accepted answer

This is true for quasilinear utility function. Suppose
$$U = d + V(x),
$$
where $d$ is the numeraire. The budget constraint is given by $p\_x x + d = I$. The utility is then
$$U = I - p\_x x + V(x).$$
Maximizing this, we have the following FOC: $p\_x = V'(x)$. That is, for a given $x$, my willingness to pay is $V'(x)$, the marginal utility.

> **Comments:**
> **username_0**: Thx, I will check your answer shortly!  

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