Apply Quotient Rule: To find the derivative of the function f(x)=xcos(x), we will use the quotient rule. The quotient rule states that if you have a function that is the quotient of two functions, v(x)u(x), then its derivative f′(x) is given by (v(x))2v(x)u′(x)−u(x)v′(x). Here, u(x)=cos(x) and v(x)=x.
Find u(x): First, we need to find the derivative of u(x)=cos(x). The derivative of cos(x) with respect to x is −sin(x). So, u′(x)=−sin(x).
Find v(x): Next, we need to find the derivative of v(x)=x. The derivative of x with respect to x is 1. So, v′(x)=1.
Calculate f′(x): Now we apply the quotient rule. f′(x)=x2x⋅(−sin(x))−cos(x)⋅1.
Simplify expression: Simplify the expression. f′(x)=x2−xsin(x)−cos(x).
Further simplify expression: We can further simplify the expression by splitting the fraction. f′(x)=−xsin(x)−x2cos(x).
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