Q. Evaluate ∫04(5e−0.25x−4x)dx and express the answer in simplest form.Answer:
Break down into two integrals: Break down the integral into two separate integrals.We have the integral of a sum of two functions, which can be separated into the sum of two integrals:\int(\(5e^{−0.25x} - 4x)\,dx = \int 5e^{−0.25x}\,dx - \int 4x\,dx
Evaluate first integral: Evaluate the first integral ∫5e−0.25xdx. To integrate 5e−0.25x, we can use the substitution method: Let u=−0.25x, then du=−0.25dx, which means dx=−4du. The limits of integration also change with the substitution. When x=0, u=0, and when x=4, u=−1. The integral becomes: ∫5eu(−4du)=−20∫eudu The integral of 5e−0.25x0 with respect to 5e−0.25x1 is 5e−0.25x0, so we have: 5e−0.25x3 Substituting back for 5e−0.25x1, we get: 5e−0.25x5
Evaluate second integral: Evaluate the second integral ∫4xdx. The integral of 4x with respect to x is 2x2, so we have: 2x2+C
Combine results: Combine the results from Step 2 and Step 3.The combined integral from 0 to 4 is:−20e(−0.25x)+2x2 evaluated from 0 to 4.
Evaluate at upper limit: Evaluate the combined integral at the upper limit x=4. −20e(−0.25⋅4)+2⋅42 = −20e(−1)+2⋅16 = −e20+32
Evaluate at lower limit: Evaluate the combined integral at the lower limit x=0.−20e(−0.25⋅0)+2⋅02=−20e0+0=−20
Subtract values: Subtract the value of the integral at the lower limit from the value at the upper limit.(−20/e+32)−(−20)=−20/e+32+20=−20/e+52
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