Differentiate w.r.t `x`
`x^(3) + x^(2)y+ xy^(2) + y^(3) = 81`

Explanation

To differentiate the given equation \( x^3 + x^2y + xy^2 + y^3 = 81 \) with respect to \( x \), we will follow these steps:

### Step 1: Differentiate both sides
We start by differentiating each term of the equation with respect to \( x \):

\[ \frac{d}{dx}(x^3) + \frac{d}{dx}(x^2y) + \frac{d}{dx}(xy^2) + \frac{d}{dx}(y^3) = \frac{d}{dx}(81) \]
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