Just in case a picture helps...
... shows the first derivative, where
... is the product rule, straight lines differentiating downwards. But,
... the chain rule, is involved - it hardly leaves a trace in this instance, but we can zoom in on it...
Straight continuous lines still differentiate downwards with respect to x, and the straight dashed line similarly but with respect to the dashed balloon expression (the inner function of the composite which is subject to the chain rule).
Writing the bottom row with a common denominator...
Then a similar routine to differentiate again...
Spoiler:
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Don't integrate - balloontegrate!
Balloon Calculus; standard integrals, derivatives and methods
Balloon Calculus Drawing with LaTeX and Asymptote!