Q. Given the function f(x)=∣x−3∣, what is the value of ∫25f(x)dx ?\
Splitting the Integral: To evaluate the definite integral of the function f(x)=∣x−3∣ from x=2 to x=5, we need to consider the behavior of the absolute value function. The function f(x)=∣x−3∣ changes at x=3, so we need to split the integral at this point.
Determining Function Behavior: We split the integral into two parts: from 2 to 3, and from 3 to 5. For x in [2,3], the expression inside the absolute value is negative, so f(x)=−(x−3). For x in [3,5], the expression inside the absolute value is positive, so f(x)=x−3.
Writing the Integral: We write the integral as the sum of two integrals: ∫23−(x−3)dx plus ∫35(x−3)dx.
Calculating Integral from 2 to 3: First, we calculate the integral from 2 to 3 of −(x−3)dx. This is equal to −∫23(x−3)dx, which is −[2x2−3x] evaluated from 2 to 3.
Evaluating Antiderivative: Evaluating the antiderivative from 2 to 3, we get −[(32/2−3×3)−(22/2−3×2)]=−[(9/2−9)−(2−6)]=−[(9/2−9)−(−4)]=−(−1/2−4)=9/2.
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