Identify function and type: Identify the function and the type of differentiation required. f(x)=8excosx, need to find f′(x) using the chain rule and product rule.
Apply chain and product rule: Apply the chain rule and product rule.Let u=xcosx, then f(x)=8eu.Using the chain rule, f′(x)=8eu⋅dxdu.Now, find dxdu using the product rule: dxdu=dxd(xcosx)=cosx+x(−sinx)=cosx−xsinx.
Substitute to find f′(x): Substitute back to find f′(x).f′(x)=8e(xcosx)⋅(cosx−xsinx).
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