Why is the f '(x) = 2xe^(x^2) the derivative of f(x) =e^(2x)?

Apply the chain rule:

df / dx = df / du ∙ du / dx

where:

f = eᵘ , u = 2x

d ( eᵘ ) / du ∙ d ( 2 x ) / dx = eᵘ ∙ 2 = 2 eᵘ

substitute back u = 2 x

df / dx = 2 ∙ e²ˣ = 2 ∙ (eˣ)²
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Remark:

d ( eᵘ ) / du = eᵘ

d ( 2 x ) / dx = 2

eⁿˣ =(eˣ)ⁿ
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